Darkle an extension like Gamification is not a trivial thing, in fact, it's a very necessary kind of extension for any community, I think if it's dropped it would be a major shortcoming for Flarum
ctml I think most of the functions could be covered by other extensions at some point in the future.
As someone who just went live with flarum after 2 years (just checked my join date, actually 4 years!) of watching Flarum grow, I'm shocked that there is consideration of abandoning Gamification. Gamification emulates the reddit upvote/downvote system, and reddit is the biggest forum that all forum softwares should be benchmarked against. The is no other extension currently, or in the future (that I know of being planned) that replicates the frontend up/down voting system that drives engagement from the user/client side. Other extensions may have more complex features, perhaps- but removing frontend interaction has a consequential impact on community engagement that I am afraid system administrators may be discounting the power of.