The original point of the GPL was to ensure that end-users retained their rights to the source code. See https://www.gnu.org/philosophy/free-sw.en.html#four-freedoms.
I think OP correctly explains the perspective of some/many/or even most authors.
Arguably, given the decline of GPL as the de facto license for OSS might indicate this viewpoint is at least an accurate perspective today and may have been the underlying truth all along. Certainly growing up I think I cared more about the concept of contributing improvements back than necessarily being able to have source to all derivative products and didn’t trust corporations to give back (I still don’t, but the situation doesn’t seem quite so serious for most projects).
Yet here is a difference between the GPL and LGPL.
A GPLed piece cannot be mixed together pieces that have incompatible licenses.
This is true even if the pieces are mixed together in a dynamic way that respects their boundaries, so that users can rebuild the GPL-ed piece from sources, make modifications, and slide the modified piece back into the combination.
This is part of the point of the GPL, and specifically that point which is relaxed by the Lesser GPL, which is called "lesser" for some ideological reason.