There is a limited number of amount of computers then you can “authorize” per Apple ID account (5).
The is a limit to the combined total of computers and mobile devices per Apple ID account (10).
There is no limit to the number of smart TVs and TV-connectable streaming devices to register with an Apple ID account.
The is however a limit for simultaneous use. Apple TV+ is streamable to 6 devices simultaneously per subscriber. (This is to accommodate for Family Sharing, which has a max group size of 6.)
Other apps and channels will have somewhat similar limits for simultaneous use; often a bit fewer streams (Netflix: 1/2/4; Prime: 2 streams, 3 devices; Hulu: 2; Disney+ (premium): 4 streams, 10 devices.)
Download and stream shows, movies, and events from Apple TV+, MLS Season Pass, and Apple TV channels - Apple Support