I follow 3d printing pretty close but can't claim to be an expert. With that said, I truly thought they served different consumer segments with the only overlap being those who bought a Prusa pre-assembled beleving it to be a one stop shop machine. Bambu is a black box from China for an end user with little knowledge or care of maintaining a machine themselves (down to printing replacement parts)
Bambu Labs' quality and feature set is much, much higher and larger than Prusa's, and the price is right. Prusa bet on people wanting to continually fiddle with their 3D printer, but that segment is already niche and likely dying off.
PEI smooth and textured. Isopropyl alcohol works until it doesn't. That is why it is recommended that you use warm water with soap. I suspect the ratio of water to soap isn't dialed in quite right in my case, but I haven't bother to fix it just yet.
Either that, or don't touch the surface with your bare hands.
I can only speak anecdotally, but I've been using this sheet for ~4 years while only cleaning it with 90+% IPA, and I haven't seen any loss of adhesion. I expect to replace it due to scratches before I have any problems with the cleaning method.