Yeah, for sure. And fans are free to follow or disregard whatever they wish.
The only problem might come in with that is some future show might upend a fan's continuity. I found that with the novel continuity I've followed the last 20+ years in the TNG/DS9/Voyager/Titan universe. Picard totally upended that, to the point that pretty much nothing from the novels can co-exist with Picard.
One can treat the whole Chekov knowing Khan thing as inconsistent, but if the showrunners consider it canon and include it with some future show/movie (granted, not likely in that case, but just as an example), then you are left with a choice to revise your own 'personal' continuity, or disregarding that new piece of information on the show.
But that choice, is as always, up to the individual fan. In my case, I can't help but think of the novel continuity as the 'prime' universe. I guess I've become too invested with that over the years that I can't help but think of Picard as an alternate timeline, instead of the reverse. Of course I know that's not how the showrunners view it. But that's ok. Just as it's ok for Steph to view the whole Chekov knowing Khan thing in her own way.