As Macs use the same components as PCs they can be just as high spec as a top end PC and the cost is very similar, the difference is Macs don't make cheap stuff using low end processors. Apart from the forget what it's call bit of hardware that makes it a Mac not a PC the difference is in the operating system and it's intended use. If Apple put a bit more effort into making Macs more gamer friendly with decent drivers etc then there wouldn't be a problem.
Traditionally Macs are not gaming machines but used in Graphic design, Video and audio editing, Graphics manipulation and so on which they are very good at and it's only in the last few years that PC's have been able to more or less match them. Unfortunately I think Apple are more interested in the gadget market than Computer games.
Personally having had Macs I would never consider using them for Games, I used mine for audio recording and editing, I stopped using Macs when they became Intel machines, mine were Proper PPC Macs ;o)
I still have my old G5 powermac tower, but the intel boxes are much better believe me ...... if you can get a modern graphics card set up on one of the 2012 intel towers its a good combo, but not for Trainz.... . Works fine on most other games , still not as good as it would be on a dedicated pc gaming machine, but more then acceptable. also one can boot into windows as well with boot camp or an emulator . id build a Hackintosh if i had the skill to keep it updated, but i dont like playing with the innards of computers, i want to use them productively .
its the OS that makes me stick with macs over PC even though i have a ROG 750 with top specs which runs Tane ok, (but it doesnt do it outstandingly better then my 2010 mac Pro) but the best thing about the mac os is I don't have to be constantly tweaking and fixing the os like I seem to have to do on windows 10.
Totally agree apple are more concerned with their toys ( phones , watches pads etc ) and this has meant that their desktops have suffered ,why on earth they cannot just make a desktop decent box with swappable parts is beyond me, which is why i stick with the older towers,.
I used macs in high end media , photography and audio for many years, and we used PCs too, at the end of 7 years the macs were still going strong and all the PC's had been junked, even tho they were higher spec'd , they also had far more technician time spent on them and they took about 10 minutes to boot up on a network as all programs had to be loaded from the server.
We found the macs much more reliable than PCs in general as they could be used as stand alone machines as well as being networked. , the extra cost was more then made up with the reliability factor. The out of box experience for setting up video editing was so much better then PC ,many times people would edit films on their home pc and then could not export them due to the fact that their machines weren't set up to correctly to do so.
For initial purchasing cost, upgradability, 3d and gaming ,PC generally wins hands down. but for ease of use and reliability ( and the lack of virus's etc) , I've found the mac a much more pleasant experience overall ( apart from trying to get decent graphics card to play trainz with