As a relatively long-term Linux user, I'd tend to say Linux is better at the things it does but not very good at things it doesn't do.
Seriously, though, the biggest gripes I have about Linux are three things: 1) that a ton of games are still Windows-only, 2) that WINE as great as it is is still a 50/50 chance of games not working (apps it's more like 90/10, in my experience), and 3) that a combination of OEMs and hardware makers are so quick to void warranties over one's use of Linux.
For (1), the situation has improved a lot in part to things like the Humble Bundle (which helped spell out that Linux users spend the most*), in part due to SteamOS, and generally in part to a lot of games being based on game engines which have always been relatively portable due to running on multiple consoles. In fact that last part is one of the major reasons why games for a long time were Windows-only: they targeted the XBox or PS/2 and were Windows-only (if at all) ports. Overall, though, the situation keeps improving.
For (2), well, WINE is still a long ways away from being a bastion of working for games. The 50/50 number I state is from my experience with ~300 non-Linux Windows games and a lot of tweaking. Honestly, I don't see the situation improving any time soon on this front, so I can only hope that either (a) the situation with (1) keeps improving or (b) we finally get a VM that does 3D right (although that'll probably take a huge shift in the 3D gfx hardware market as secure isolation is a big root of the problem).
For (3), it just sucks. Thankfully it's often cheaper to custom buy one's hardware from a small shop than to go with an OEM (exceptions for laptops and very low end setups (<$400)).
Honestly, though, I switched to Linux because as a programmer it just made sense to me that if I'm going to use an OS that has bugs, and all do, that if I ever got to the point that I was really frustrated enough to work to fix said bug, I could actually reasonably do so without threats of lawsuits over claims of extortion, anti-reverse engineering EULAs, or the hassle of binary hack debugging for years**. So, to me that's the reason open source is generally better. But, that's definition a YMMV.
* Lying with statistics. 1-2% of users use Linux (excluding Android, iOS, etc which are a whole other thing). Linux users pay ~50% more. So, effectively 1.5-3% of Windows users in aggregate. Take the fixed cost of porting software (and hopefully the low variable cost of continuous support), and you've got an idea on if it's worth it or not.
** Because a rom hack targets a specific version, but OS files can update regularly totally breaking any sort of binary auto-patcher. Same could be said of a software patch, but then most open source projects aren't hostile to incorporating a software fix into their repository...unless you go out of your way to intentionally antagonize them first *then* submit a patch.