Bitcoin growth as in what? To me it is growth as in more players but it is a rollback on the other hand because more Bitcoin is placed into the same hands of central players. It is growth if you tell me millions of people are now becoming new Bitcoin holders, not when I hear banks and governments centralizing all those funds in a small number of hands.
Countries and governments join this market bring double effects. First it brings more legality and legalize Bitcoin more as well as contributing to new big demand that will lift price up. Secondly it might bring negative effects by having more big holders and Bitcoin distribution will become more centralized in no longer institutional investors or old era whales but with appearances of governments.
Governments surely will not be actively with trading and their Bitcoin holdings will reduce circulating supply on the market that can possibly affect trading volume on the market too.