Yup, at that per episode cost Academy needs both the "long time fans" and "new fans" to show up in numbers.
It's effectively like running a government with the mentality you only need 25% of the vote, call an election, then get gobsmacked that you need to win over near 50%.
Modern Star Trek is often accused of being "review bombed" but it seems like the fan ratings reflect the quality of the shows pretty well, while the critics just give every show positive reviews.
Your average critic is going to be a generalist. Their target audience just isn't the existing Star Trek fanbase, and they have tons of new content to cover. Most new content wouldn't have gotten off the ground if it was rotten to the core. Instead, most streaming series tend to start off okay, then collapse later on.
Modern Star Trek has a targeting and a budget problem.
During the Berman era, Star Trek was on broadcast TV with the goal of producing enough episodes that could be stripped in syndication. So airable at 6pm and without too much continuity that a casual viewer could end up lost if watching not just a random episode, but a random episode in progress. 22-26 episodes a season, which meant quantity over quality and the need to make the schedule even if a stinker was in the pipeline. The "airable at 6pm" part inherently came with some standards and practices restrictions. And the "broadcast" part meant it had to appeal to a broad audience around the country, not just a deeply concentrated audience is say New York and California. So you have another inherent limitation to not get too political to the point of becoming partisan.
Berman era also had the goal to both appeal to the fanbase while being broadly acceptable to the casual viewer. The fanbase provided all the auxiliary merchandising revenue that allowed the franchise to
punch above its middle tier level and net Paramount even more profit.
And, yes, there was a gradual viewership drop off. But much of this was due to expanding television options in the US as cable took off, and UPN limiting Star Trek from pursuing serialization when that was starting to take off.
Whereas now you have the Kurtzman era. CBS All Access / Paramount+ kinda is the UPN of the 21st century. The TV shows are high tier budget for streaming, only below HBO / Amazon / Netflix flagship levels. But the budgets just don't match the audience.
The Kurtzman era is divisive towards the audience. Too many existing fanbase fans have been alienated without an in-kind greater replacement from a new audience. Merch sales are definitely off. The strategy just isn't working. While some Kurtzman fans would like to just gaslight others over this, it can be objectively observed.
Okay, and? That happened consistently to the shows after TNG. It's hardly a new trend for the franchise.
Just imagine how insanely profitable TNG was for Paramount at its peak... The Berman era ran from when the Fox network was just one night a week, cable TV was in its initial buildout, and VCRs were still a new thing to the multichannel cable / satellite era.
Regarding ENT season 4... was it still profitable for Paramount more broadly at the time (in the UK, it aired on Sky One, which was known then for paying good money to get the rights for American TV shows away from the BBC/Channel 4 etc)? For UPN? Wikipedia claims that when ENT was canceled, it was still UPN's most highly rated show, and ENT did have the noticeable budget cut. Scott Bakula has apparently claimed that had ENT been syndicated, it could have easily gone the full seven years.
The second half of the Berman era was really marred by UPN's format meddling. And it didn't likely help that in the end rumors hold Les Moonves had multiple clashes with Rick Berman over trying to fire Scott Bakula, and Berman held his ground, contributing to the cancelation.