We will never see 26 episode seasons again.
It currently takes more than one week to shoot a 42 minute episode.
Also, actors are not willing to lock into shows that leave them unavailable for movies or other television shows.
Star Trek and other streaming series are able to cast A-listers not just because they are willing to pay high pay rates and list them as executive producers but also because the A-listers are able to lock in multi season contracts with Star Trek while still being available to do other things.
But 10 episodes is not the maximum possible. Large ensembles like Starfleet Academy have enough main cast members that not everyone has to be on set every day.
As well, it’s possible that 4 or 6 episode limited series might be the perfect vehicle to bring back a Legacy character or explore something like the Department of Temporal Investigations. Under the old management those weren’t negotiable.
Why Paramount had such a bizarrely rigid policy after the ViacomCBS merger has never been adequately explained.