If the leaked roadmap holds true, and Gen 10 is followed by a Legends Galar game, there's a chance they'll miss the boat on a nostalgia cycle BW cash-in. The best bet for Gen 5 is putting the original games on Switch. It would help keep Unova relevant and accessible, and it would give GF and TPC concrete data about player habits and the popularity of each game. Vocal fans don't always show up, and 2010s sales data doesn't reflect 2025 demand. Having current player data for all the classic games would be invaluable to TPC and GF. If BW and BW2 are accessible and widely played, it could open the door for a proper BW3 sequel. Z-A proved that Pokemon sequel games are viable. It was a risky project, and wouldn't have been greenlit if XY sold BW numbers. That kind of risk-averse planning is probably why a Legends Galar game is in play, despite it being too soon for Gen 8 nostalgia. Switch Pokemon games did gangbusters, so the bean counters determined Galar was the least risky. As a fan, it certainly seems risky to revisit Galar given the sour reception to SwSh, but once again, the sales data speaks louder than the vocal fans.
I'll point one note in which you may be missing out on.
We're approaching the timeframe where almost all of the of the intended casual buyerbase (aka, kids and teenagers, not 30+ year old adults with nostalgia glasses) have had their first experiences of the game with the Switch. I'm speaking of the kind of people who buy pokemon "cause it's pokemon", and whose main gameplay approach is "beat the story, maybe whatever postgame story there is, then never touch the game again if not to run around with their lvl 100 Greninja for 4 hours punching wild pokemon (totally not my nephew on that last one)"
These players are used to the modern pokemon gameplay loop, no grind, easy and clear to follow instructions, map pointers of where to go, openworld or semi openworld structure, intuitive battle system and UI, etc.
These players don't... actually care for remakes at all. They care for their shiny new toy they will be able to hug as plushie later down the line. These players are also likely to have started playing pokemon with Galar itself so grown attached to some of the new Galar pokemon. It's reasonable at that point, from raw capitalistic standpoint, to try and bank on this new generation of nostalgia, rather than from the growingly disconnected adult playerbase.
Expecially after BDSP's relative flop (not that it didn't sell, but definitely wasn't received as well as any other remake), and the overwhelming success of both the Legends games, I can definitely see GameFreaks / TPCI seeing that in the bigger picture, Legends independant games are the correct way to revisit places. And on this point, Galar offers a lot of interesting choices: you can either go in the past (explore the history of the "original heroes", or how Eternatus and Dynamax came into existance) or in the future (what is the aftermath of Rose's arrest? What's been of Leon? Has Calyrex finally found peace? Is Peony still stuck in the Dynamax cave for the rest of his life searching for his poor girl?). Gen 5 world already sorta did this to itself since BW2 are direct sequels of BW, and as I was implying earlier, at this point they're mostly unknown entries that "exist" with the modern fanbase having little interest in going back to them.
And as extra, Legends games do offer the option to introduce new pokemon and regional forms (megas included). Remakes do not. That too is missed sales, because even for the more hardcore/competitive playerbase, even with the implication that with grinding you may be able to "buy" all pokemon in Champions, having them readily available on demand by just... owning the game is a pretty big deal. Let alone collectors who like to have a full pokedex in Home (living or not).
(On slightly related note, I find funny how BDSP did deliver in the request of giving us stronger, harder story battles, with many Gym Leaders having overtuned competitive-ready strategies, and that was actually one of the most disliked features of it I can read around of. Pokemon fans truly can't be pleased)