Another point that Spielberg brings up here is that many studios nowadays are only focused on blockbusters and branded IPs, and are uninterested in smaller films.
These films that studios used to pickup for prestige purposes are now going to streaming services.
That’s where streaming services come in if a filmmaker wants their vision to be seen.
Steven Spielberg notes in the interview that he released The Post theatrically and not on a streaming service, but he’s Steven Spielberg; not every small film with a lesser known director will seem financially viable for a studio to release it theatrically.