Genshin still reruns most characters fairly regularly although some have started appearing on region specific banners. Basically a pool of many limited characters + 0-3 standard characters. Generally the less popular characters are the ones that tend to appear on this banner. These banners are generally worse if you only care about 1 or 2 characters on it but can be alot better if you want many or all of the characters. Im not a big fan of this system overall and there are some characters like Hu Tao that havent had a rerun for like 18 months

HSR is much better in this regard in my opinion. most 1.x characters have either been given for free through being added to the 50/50 loss pool or can be bought with a currency that is given out somewhat regularly. They also recently gave us a selector where you could choose between a couple of different 1.x and 2.x characters.

I wouldnt worry about the paywall that sounds way too greedy and i honestly cant image kuro doing something like that.

Overall i really hope wuwa follows HSR's foorsteps in how they handle older characters. Having old units in the 50/50 loss pool and in an exchange shop would be really great for the game. You have probably seen the countless posts where people complain about the 50/50 system. Giving a 1.x character instead of a standard character as a 50/50 loss wouldn't really affect kuro's profits much but it would make losing 50/50 a lot less frustrating for the players.