The schools I attended from the late 80s through mid 90s had 5 to 10 Macs for every PC. In spite of this, there was usually a wait for Macs but never for PCs.
After we graduated, we found that the business world was 99% PCs, as it had been from day one, never having given Apple any serious consideration at all.
Most then went on to get the same kind of computer at home that they used at work because, as much of a pain as it is to use Windows, it's more of a pain to have to use both.
Then school boards started making noises, with some merit, that kids should learn in school what they'll be using in the real world. This caused many schools to switch to PCs.
This has nothing to do with technical merit and everything to do with first-mover advantage in the right market (personal computers for business).
Also, running virtual desktops over the network is not necessarily slow and clunky. Have you tried it? I've been doing it for years.