Too Long; Didn't Read
Vitalik Buterin says he is perennially more sympathetic to the concave approach than the convex approach.
He argues that the Bitcoin ecosystem's temperament is much more fundamentally convex. But not everyone seems to share the same broad intuition, not everyone shares the same intuition.
He has argued for moderation in Bitcoin block size debates, arguing against both 1-2 MB small blocks and 128 MB "very big blocks" in the DAO fork, but to many people's surprise, also argued against similar hard forks that were proposed more recently.