lol. Sorry pal, I don't game on my macs. I game on my xbox360 and ps3, however. Try again.
Don't know about you, but I'm a huge PC gamer. I mean, why bother upgrading a 10 year-old PC if you're not going to do resource-intensive activities?
I admit, every once in a while, I do get tempted to buy another iMac just due to how aesthetically pleasing it is. However, at the end of the day, I'm a man and I care more about power, stability, security and functionality over looks.
And trust me, it's not just Steam. Sony Vegas is another app that doesn't work on macs.
The difference in dev support between windows and macs become even more apparent from 3rd party applications from companies, groups and individuals that aren't well-known but fit your own personal niche. Take Desmume. Though they do have a mac version of their program, it has far less features than the windows version and it's heck of a lot unstable.
Let's start with your ignorance.
Steam is so buggy in general that they have an entire forum just for windows-related errors.
http://forums.steampowered.com/forums/forumdisplay.php?f=17
Actually, that section is devoted to any type of help and tips, not just technical errors. Take a look at the topics that people post.
Steam Account got hijacked - Does this sound like a windows-related error?
Pink/Black squares on Gmod Addons? - This is an add-on from another 3rd party. Not Valve's problem and it's mostly due to programming flaws rather than windows flaw.
[TF2] Everyone can connect to my server except me - Not a windows problem.
Why won't steam launch a game? - Maybe.
Gifts from German - Nothing to do with windows
Help! Steam Uninstalled it self! Now it is just being... - Ok, I'll give you this
day z problems? - Not a windows problem. 3rd person problem is due to coding errors by dev.
Games crashing/not working after MvM Update - I'll give you this one
Team Fortress 2 - Crashes whenever I play it. - This too.
What happened to"Battle versus Chess"? and no key? - Not a windows problem
Can't buy a game - Not a windows problem
Did I just loose all my money? Paysafecard problem - Not a windows problem
You get my point. Now let's have a look at the mac section.
Wil PayDay The Heist work on my Mac
Steam client not working on MacBookPro - Mac problem
[BUG] Some games don't download in OS-X - Mac problem
Losing Non-Steam Apps added and corrupt icons. - Mac problem
steam error code 118 fix? - Mac problem
Validating Steam Cache Files - ???
[BUG] Error/Crash Reporter Opens When I quit Steam - Mac problem
Steam store 000000s - Mac problem
Mountain Lion FM2012 - Mac problem
Macbook Pro and Heating Problems - Mac problem
Launching game doesn't work - Mac problem
CS: GO for Macbook Pro 2010 - Mac problem
Texture [BUG] - Mac problem
Blank screens, steam overlay failing, unresponsive screens - Mac problem
The list goes on.
Note that I didn't cherry-pick the topics. They were all on the front page. You should also note that mac users only make a tiny portion of Steam gamers yet make up the vast majority of bug-related complaints. One can safely arrive at the conclusion that Steam is more unstable on macs than it is on windows.