If remaining active members of these clans are quitting, that is a problem, but I still feel like the checks are lenient enough for those people to turn it around if they really care about their clan. The only real differences between official clans and unoffical clans is that official clans have their own subforum, and I don't see why 5 people need a whole subforum to themselves. After failing the checks, they will still have their clan, their clan thread, and the ability to communicate on other platforms like discord.
I don't feel like these activity checks are purposefully designed to catch clans out, they just catch extremely inactive clans that don't deserve to remain official, in my opinion. The clan checks were done by humans before, but it relied on unpaid people taking their time to do it, and the checks weren't always being done. The current system already gives a clan 2 months to sort things out.