If I recall right, we asked to the Support Centre of Turkish servers in 2018 and they said that it wouldn't affect the game at all. Probably they have already prepared a migration to html5 or Unity or some other counterpart in these 2.5 years or will do in the following months, especially when we consider the Naruto Online Mobile being released.

Having an official declaration would be nice tho, Flash is just so full of bad optimizations and security/consistency issues that many of us observed/reported in the past that I'd say the game can only be better than it is.