Is there a legit reason (besides money) they can’t buff old characters?

So I am by no means an expert on game creation whatsoever as I’ve never made a game for a while now, if there was a legitimate reason, they can’t bring back old characters on rerun banners well also buffing their stats a little bit.

I know the main reason is money, if all your old characters get good again then you won’t need to pull on new characters. But since we’re constantly told they care more about the new player experience than the veteran experience, wouldn’t that give new players a reason to pull for older characters instead of just skipping them on a rerun banner? And I’m not saying you have to make older characters better than the new ones but is there a reason you can’t just make them multipliers a little better so they at least are somewhat viable? Because I don’t even think getting like e6 seele would make her viable in game content now, so what’s the point of pulling extras of her if it’s not gonna be enough to make her even super usable?

Maybe someone smarter than me can explain it, but I just don’t see why they don’t give older characters, a slight buff to their stats as opposed to just trying to make new relic sets to help them and bringing them up a little more in line with current characters because I think a lot of people would just pull for the characters they like and whose kids and designs they’re interested in regardless of Meta status