While I think readers of the Litverse stuff not moving on to the new tie-ins won't be uncommon, I think the rest of your story is.
I don't have a fan wide survey to back this, but based on what I have seen in this forum, youtube comment sections, and reddit, I think the numbers of readers of Star Trek novels that are not Star Trek fans is a fairly small percentage.
The reason many people are not going to read the new tie-in novels is because they are not interested in the new series; the "Not My Trek" people which happen after every new series is launched. They are usually still Star Trek fans, just fans of TNG or DS9 or TOS or whatever and not the newer stuff, and will still be fairly plugged in and knowledgeable about the old. I think the number of people who are no longer fans of say TNG or DS9 but still read the novels of those respective series would be rare.
All of that said, the fact of the matter is these tie-in products exist primarily as a means to sell the series they are based on, so the focus is always going to be on maximizing that potential. We are lucky that the last 20+ years Pocket Books has also gotten us authors who care enough about the franchise to keep the quality so high, but at the end of the day they are going to direct those efforts primarily to the series currently airing to continue to build up fans for those series. This has been the case every time a new series has launched, and it's not different now. I think what people have said is likely to hold accurate, we will get a couple of books each for Discovery, Picard, and Section 31, and a couple of books for TOS to hold everything up. With Picard being one of the series, maybe we'll get a TNG novel here or there in the same style of the TOS novels, or perhaps when important anniversaries hit, but I think the efforts are going to be tie-in media that have current media to tie in with.