Since the new role lock system in Overwatch is active, some players apparently have problems with it. This includes professional player André “iddqd” Dahlström, who at least predicts the end of the game for himself.
This problem is seen by iddqd: With the new “Role Queue” in Overwatch , players must choose a role before the game: DPS, healer, or tank. Two of each role are needed. However, this sometimes leads to long waiting times for some players.
In his stream, iddqd explained that nobody wants to watch a streamer when he is waiting in line for two hours, no matter how good he is. For him, this is the case. Although he is a good DPS player, he can no longer play his role.
What is killing the game for me at the moment, and what prevents me from waking up and wanting to stream Overwatch, is knowing that I can’t play my DPS. […]
Players love to see me blow heads, and believe me, I want that more than anything else. But what if I really can’t do that anymore? What if the game physically does not allow me to? What do I do then?
iddqd via Dexerto
These problems still exist: The long waiting times are not the only issue with the new role lock. Due to a bug, it happened that all players could compete against each other – even the weakest against the strongest.
This led to the ranked ladders for Season 18 being temporarily disabled.
Is Overwatch really dying because of the feature?
This is the situation with Overwatch: Talking about the downfall of Overwatch is perhaps still a bit too early. At least the numbers on Twitch have remained consistently high for about a year, with fluctuations of less than 1% in average viewers (via sullygnome).

Additionally, Blizzard already has further plans. Overwatch will be released for Nintendo Switch in October, which many players and fans are already looking forward to.
For professionals like iddqd, the role lock could indeed mean the end of their careers and interests, but Overwatch itself seems to be doing quite well at least for the moment.