The VM is optimised for the OS, the OS is usually a fresh install with just that 1 program you need to use instead of you're entire life scattered across the desktop, it can be a snapshot of the system in an optimal state right after running an unfuck windows script that removes default system malware which doesn't let it reinstall, it has less system resources to deal with for the simple fact it can't use them all at the same time as the base OS.
it's not a drop in replacement and anyone looking for one will be disappointed by literally anything available.
You're learning an entirely new operating system, don't think of it as an upgrade, this is a time sink. You'll be under the hood more than on the road for the foreseeable future, but what's the alternative?
it is my contention that you could eat any random items form the perimeter of the store and be healthier than anyone that buys items from the health food aisle.
Food is an ingredient, it shouldn't have ingredients
...or as I've come to call it grep+linux