I understand the logic, but I wouldn't be surprised if other major campaigns also decided to switch to stablecoins (due to the unpredictability of BTC fees), in which case, either Mitchell would have to change the policy for his Overview thread, or we could need a new summary (perhaps in the Altcoins section) that includes all types of campaigns.
Strictly speaking, only one campaign is entirely a Bitcoin campaign. Where the payment rate is in Bitcoin and not in USD. The service section is much more "popular" than altcoin/bounty, so everyone wants to start there.
However, this is a Bitcointalk forum, BTC and altcoins should not be equated.