Sure, there must always be a challenge, but there is no challenge in using weather. It's just an automatic win condition, that's all there is to it. There's absolutely no fun in it. Also, Genesect was not impossible to prepare for. Excadrill was not impossible to prepare for. DPP Salamence was not impossible to prepare for. Something "not being impossible to prepare for" has never been a good argument and never will be. If anything, I'd argue that weather encourages uncreativity since you can just use the same cookie-cutter Rain team with a few changes, click that button that says "Hydro Pump", and win. Then, every team has to dedicate some slots to beating the cookie-cutter Rain team, as well as the cookie-cutter Sun team, and the cookie-cutter Sand team..... Fuck, that's already a pretty big burden on team creation. Point is, nearly everything in this generation is cookie-cutter.