Surely a sensible compromise would be to have previous season rewards obtainable via other more grindy means? For example if for whatever reason you couldn't play FFXIV for a couple of months and ran out of time, have some kind of histroic vendor where you need to spend a bunch of wolf marks or trophy crystals for older rewards. To be clear I emphasize the grindy part since I agree to some extent that giving out the rewards for little to no effort after the season would make the season itself pointless, although I will say I've never been a fan of these 'Battlepass like' systems so if I had may way it would never be in the game. Having content that is time gated (excluding yearly events) is nearly always a terrible idea.