Now onto my response:
TV has always been this way, the only difference is there aren't time slots now, so they can develop a bunch of crap shows (that used to just get left for dead after pilot season), let them run for a season/series and gauge popularity vs cost, and cut the under performers (why I don't watch a show until a couple seasons are live).
When it was ad-supported with 4 prime-time hours across 10-ish channels (between OTA, cable, and premium), every show had to count. Streaming removes that constraint, which has actually been beneficial to producers and consumers of content. More shows means more jobs for writers, actors, directors, crew, etc., even if those shows they are working on are completely forgettable.
But with every gold rush, comes over-abundance of people panning for gold. So yes, there is an over-abundance of screenwriters. There is an over-abundance of choice on the platforms. There is an over-abundance of platforms to chose from. There is an over-abundance of over-consumption of content on these platforms.