1rkhachatryan
Call me Robert guys
Turn limits definitely decrease the effect it'll have. Protect will too, with Protect you could theoretically already stall out two of the three turns. In doubles Fake Out is also going to strip away the turns. And I believe Roar simply switches the dynamaxed pokémon out and cancels the dynamax altogether.
At least in the gyms and raids, I don't see the roar thing working, in raids there's only one pokemon and in the game we've seen so far, the gym leaders dynamax their mains which seem to be the last pokemon. I'm not really sure to what extent dynamax will be a thing in online battles so it could be a thing there.