I would like to second this
so strongly
People act like Bug needs to be buffed offensively, but that implies Pokémon don't
use Bug moves by choice
all the time
The best example is the case of U-turn vs Volt Switch - even though Electric is superficially a better attacking type and Volt Switch comes
pretty close to being available to every single Electric-type (it's not fully universal, but there were
very few exceptions before the last two Generations), U-turn is such a vastly superior move that it's even preferred by many of the Electric-types that have both, even though Bug ought to be a "bad" type and Electric is what they have STAB on
In a particularly extreme example,
Tapu Koko's sample set in current-Gen OU recommends U-turn over Volt Switch despite having Electric STAB, the boost from Electric Surge, maximum Special Attack EVs and
a Timid nature, factors that mean
that exact set using Volt Switch instead would do just
over 2.35 times as much raw damage on a neutral target
This is not an accident - U-turn
is still a better move than Volt Switch
When a Pokémon uses Volt Switch, it commits to doing damage and switching out if the opponent doesn't send in a Ground-type but staying in and doing nothing if the opponent sends in a Ground-type (one of the type's expected losing matchups), which is the exact opposite of what most Pokémon want out of a pivoting move
Conversely, U-turn can't be blocked by
anything, and it takes a
lot for a Pokémon to give that up if it has the option at all
That's the thing: U-turn isn't used primarily for damage or good matchups - it borders on being one of the "safest" moves in the entire game, and it's appreciated and readily utilized by nearly everything that has it, Bug-type or not (and physically offensive or not!)
This matters so much more than people seem to realize - being weak to U-turn is rare, but it also borders on
crippling, because Pokémon are
afraid to invite U-turn or to be threatened and forced out by the possibility of U-turn
Conversely, being resistant to U-turn may be common, but it is also
coveted
People often complain in particular about Fairy being given a resistance to Bug
(even in this same thread, people have suggested it was some kind of stock resistance to "pad out" its defensive profile without hurting a more popular type or one that was meant to have minimal implication), but that's another thing that needs to be looked at more closely: Fairy's resistances were openly designed from the ground up to make it "the anti-meta type," with particular focus on the types that were most prominent in Gen V VGC and probably with Gen VI's Dark buff in mind as well
It resists Bug
because Bug-type moves are meta, and it's actually considered one of the most relevant and useful resistances Fairy has to offer: it means they don't take excessive damage from it every time something they intend to counter tries to pivot out of them, and they can also switch in safely to resist stray U-turns aimed at other Pokémon
Essentially, Bug is the type that's "allowed" a crazy-strong tool like this
only because it is one of the worst in offensive matchups alone - these are not unrelated!
The thing is that
Pokémon care about their defensive Bug matchup because of the universal utility of the most relevant Bug move
and you
can't simply give a tool like this to just any attacking type without a harsh drawback
(like making Volt Switch fail on the Pokémon its users would most want to escape)
Even the more recent Flip Turn on the more "powerful" Water type had
extremely careful distribution compared to past pivoting moves and a power decrease to match
+ also Water Absorb and Storm Drain may be relevant depending on the format (I think Storm Drain is quite common in the official competitive format, VGC, and it also happens to block Flip Turn from anywhere on the field!); conversely, no Bug immunity exists even with any Ability, because it's a major part of the the identity of the type to be "offensively weak but perfectly reliable"
The type chart is a lot more carefully considered than people give it credit for, and it's incredibly rare that I see someone ask to "fix" it and actually agree with their suggestion
The "problem" is when people look at matchups like they exist in a vacuum and every type needs to be perfectly balanced
before any moves or Pokémon are made, when moves and Pokémon belong to specific types because of what those types can do for them and what part of those types they represent
"Weak" types on paper are usually the ones with the strongest assets or the strongest Pokémon - moves and Pokémon that rely on having constraining matchups to be kept in check - and there are Pokémon of
every type that see in-game and competitive success when they work with the type correctly instead of trying to shape it into something it's not, so obviously this is working!
If you want to buff Bug-types, you should absolutely not do it offensively, because Bug's most defining move and its entire mechanical identity leans heavily on the offensive matchups that it already has and it would be very easy to bring about some pretty stupid consequences if you make it better
On the other hand, Bug is a pretty
fine defensive type anyway - when specific weaknesses are patched up by the right secondary type, held item or partner, it is usually more than workable and you can really see the type's distinctive toolkit shine through
A lot of Bug-types' identities come from their moves most of all, many of the best of which are rarely distributed to other types
None of this is stuff you could get just by looking at their matchups on a chart - you need to look at the Pokémon that have the Bug type and what they do, as well as the Pokémon that run Bug-type moves and the Pokémon that match up well against Bug-type moves and how much that is valued, before you can write off the type as flawed or in need of saving
Basically, I don't think you
need to "fix" the type; I think a lot of people just look at the type chart in an incomplete way that doesn't reflect how well it's really designed
(my unpopular opinion: the type chart, in its current state, is one of the coolest things about the series and is the underlying factor between almost all of the other mechanics and design choices I like the most; I wouldn't change a thing about it), and I wish more people would focus on understanding it before they try to correct it, because uuusually the latter means making it worse