They are giving out ways to obtain previous a previous year's evo building, such as the Red Chocobo to newer players, hence, there is no inherent 'disadvantage' anymore. Just be patient and eventually, with enough farming, it's possible to get a Lv10 Hothead even if it takes 1-2 years to achieve...
BUT!
We ALL know that the game at this point is heavily rigged *
against* the players, especially the late game, Ch16+ players who have seen their costs across the board skyrocket, while production is in no way keeping up...
Newer players have options being in early chapters, but even by mid-game, if you've placed too many expansions and/or invested too heavily into AW's, you're just completely screwed in both the tournaments + spire play.
Hence, at this point we NEED new combat bonuses from event buildings to at least bridge *
some* of the current gap, since we all know that the devs will likely not revisit the formula for at least another 2-3+ years. (...if ever, since apparently we filthy power gamers were never meant to obtain 8-10k and higher tourney scores!

)