Well, since you really want us to talk about how our submissions affected the metagame...
Firstly, my Relicanth honestly is one of the best support you could ask for if it existed, due to spore and glare, as well as defensive barrier. I could see someone sending this out first because of that bulk and stealth rock. It deals with both primals pretty... Uhh... Alright as best, but stuff about them that really annoys it is Primal Groudon that is the solar beam variant, and Primal Kyogre gets lucky with thunder.
As for whether you should go for spore or glare, it depends. You could use spore for Lugia so that it can't phase away your Relicanth before it sets up defensive barrier (do watch out for Toxic though regardless as it is slower than all the viable ubers), or generally any mon, but only one because sleep clause but it does best at trolling Lugia, or you could use glare to try as an attempt to ignore sleep clause, but paralysis isn't quite as busted as sleep as you can still do stuff with paralyzation, but it's just the paralyzed Mon being slower and it's only a 30% chance it will stop it from moving.
Defensive barrier can be great for giving Relicanth more bulk to use it's support better for 2 turns (4 with terrain extender), or if you was to run terrain extender, support sweepers that you may have. Also with terrain extender it let's Relicanth use it's supporting moves more, but granted if you want a true support move then this is the most supporty you'll get of all moves.
Now, this thing has rock head head smash for a good reason: So it's not taunt fodder. Most support mons are complete taunt bait, and while this will lose it's other options and is slow enough to get taunted by pretty much everything that can taunt, it still has head smash so it can still do stuff, even when taunted. Although if it gets taunted it becomes primal groudon bait, and that is the most dangerous Mon in ubers.
It's bulk can be pretty good too, because it can live a hit from xerneas and glare it, or use spore on it, but that's only with special investment. It can take a hit from Rayquaza and use status or head smash to do major stuff to it. And Ho-Oh? Don't even think about Ho-oh vs this thing, one head smash and it is dead. However, it does get balanced out because Lugia can toxic it and it's HP will go down more and more, and if it was to play mind games via using whirlwind, you can forget about defensive Barrier if it predicted that. Furthermore, it gets smacked by solar beam primal groudon, takes major damage but not OHKOd from a groudon's precipice blades or earthquake, and gets beat by it no matter what if it was taunted, hates Primal Kyogre loving to run thunder, it is stupidly slow, slower than dusk mane Necrozma even, so uhh swords dance and then an earthquake or it's Z move is going to nuke Relicanth, and since Relicanth is slower than it, it will get to use one of those 3. And if Relicanth already used spore on something else, then it can set up and kill very safely, and do NOT use defensive barrier against this thing if you can't put it to sleep and glare hasn't been used on it, as it can just set up to +6 and steamroll your team, and who knows it may be a ultra Necrozma so that'll stop primal groudon and yveltal if it is, but you do not know which one it is! Lastly, never let this thing eat a grass move, as it is 4X weak to it, although this one isn't a big problem as the only real uber that is a grass type is Shaymin sky, but it's not super dominant or anything like that, so you don't need to worry too much, although you still shouldn't let this thing eat a seed flare.
Overall, it gets balanced out by being big primal groudon bait, being primal Kyogre bait, having to guess what Lugia is even going to do a majority of the time, being bait for Dusk Mane Necrozma to sweep, and unlike Lugia who is also really bulky, it has no reliable way to recover, and any grass move will just splat it dead, while at the same time it has enough bulk to use it's tools effectively, can take on Rayquaza with ease, defensive barrier with terrain extender can really help you're team out, head smash makes it not complete taunt bait, it can utilize 100% accuracy status, and set up hazards. Overall, yeah it gets balanced out from it's upsides and flaws.
