The difference between FOSS and proprietary (to me) is the motive. FOSS projects are often created out of a genuine need/want to solve a problem. Proprietary may also be trying to solve a problem (we can't through all of them under the bus because we live in a capitalist system which limits our options, we need to survive before thrive). I still find that proprietary often is just created for profit, and as profit motivated software it has an incompatible goal to actually fixing the problem.

A good (profitable) proprietary app won't fix any problem, but instead exacerbate it to maintain the reason for its continued existence, all while eliminating competition.

I'm also not too happy with this framing of the free software movement. The goal of the software freedom movement is to empower users with the freedom to use, modify, and share the software; that free software projects end up being alternatives to proprietary software products ("paid" is irrelevant) is more or less a consequence of people scratching their own itch. Maybe the fact that GNU and Linux started out as attempts to clone the proprietary Unix operating system furthered this view.

I don't think it's helpful to look at free software projects as being "alternatives" to popular proprietary software, because this means that even the best free software will forever be in the shadow of its proprietary counterparts. For example, if you have a proprietary program X and a free program Y that does 70% of what X does, you'll be inclined to judge Y unfavorably - but if that 70% covers what you need from program X, then program Y is an acceptable replacement for you.