LRC best on PC or Mac?

"LRC constantly crashes on my PC.  I'm thinking about trying a Mac M2." Given the heavy lifting from PC to MAC in general, I suggest waiting since it's still the early days of 13 (poor choice in numbering. They maybe should have skipped to 14). You mentioned your video card but it may be something else in the OS and/or hardware so you may want to check any crash reports and/or the Windows Event Manager to try and pinpoint the culprit. Just my 2 cents. 

LrC crashes on both, in some situations. There has been no study that I know of that determines which crashes more. If you are having problems, a brand new computer ought to fix that, but there's no way of saying that Macs are better than PCs on this. People who have brand new Macs show up in this forum to complain it is constantly crashing.

The idea that you are having trouble on a Windows PC, therefore the problem must be Windows and switching to a Mac will solve the problem ... is incorrect logic in my opinion. 

LrC has never crashed on my Windows computers.

I have noticed that just about everyone who provides video tutorials for LrC uses a Mac. Personally, I have used LrC (and Lightroom previously) on PCs for the last 10+ years and have never had problems. Currently using 13.01 and don't have any problems with it crashing. I don't have a stellar PC; just 16 GB RAM and only a partially compatible video card. I know, not a very helpful answer.