PMC are “salaried mental workers” who reproduce the essentials of capitalism without owning the means of production,

The PMC very frequently overlap with the petit-bourg, many of them are landlords, and most of them have pretty significant assets. The latter is a relatively recent phenomenon because access to capital markets is so much easier now than it was even 20 years ago, let alone 100+. If you don’t own any individual means of production, but you have several hundred grand in a stock portfolio, you still reap the rewards. A lot of class analysis ignores this point and just pretends that PMCs are just workers like me and you.