Yes, that is just you (and a bunch of other people).
APS-C sensors are cheaper to make
Differentiation. As long as you have an APS-C model in the lineup, FF can be treated as a premium feature and you can charge more for the same or even worse overall performance. They have been able to charge a premium in DSLRs and now the R5 and R6 come with a much increased price compared to the 5D and 6D in many markets. Canon will want to be able to keep charging as much as possible. The RP becomes a moot point being based on older sensor tech and will, if it remains in the lineup, be seriously outperformed by a similarly priced APS-C model because it will at best be an entry-level FF body.
because the competition offers APS-C models in their main mount.
Because FF isn't as big a deal as it was as the greatest advantage is lost; a big nice viewfinder can be had with any sensor format when you have an EVF (and that "FF look" really doesn't matter all that much to most people and to those who crave it, well, just pay a premium to get it)
Do you recognize why people bought the 7D rather than the 6D, 5D or the 1D? If not, well, too bad.
Why bother with the 135 size sensor anyway? There are larger sensors available, not like there's anything magical about this particular size. Too large to be compact when taking lenses into account and still not large enough.