Okay, but why would you? What's the advantage of that? VSTs are resource hogs (when you have like 10+ running at once), not DAWs.
I somehow doubt a full-blown browser connected to more than a couple of VSTs would be less of a resource hog than doing the same in a DAW. On your computer. That you own. In your house. Without like additional 50ms of latency for the data to travel to the server and back.
Considering when the standard was written (v2 in 1999 and v3 in 2008), what else would they be?
As horrible as it sounds, a VST is just a .dll file you're running straight from the Internet. On a "positive" note, they're backwards-compatible with like Windows Vista!