I'm a bit confused by this statement. Isn't GURPS EXTREMELY mechanics based? I can figure out the penalties for shooting a guy in the left eye as I speed by on my motorcycle at night. The combat is extremely detailed relative to a system like D&D which is more abstract. I know if you buy the advantage wealth in GURPS, it gives you multipliers for your starting wealth. It's entirely up to the campaign and how it's run whether you need to account for all of that spending or not. Typically if you're a millionaire, I wouldn't bother with normal purchase accounting. There is a published rule for abstract wealth to avoid this accounting. I feel like GURPS is pure mechanics, and you bring your own settings and feel to it.
Sure. The rules on firearm damage by caliber aren't relevant in a Cave Man RPG. The super powers can't be used in a setting without super powers. Ignore the magic systems in a cyberpunk game. GURPS is pure mechanics without assuming a setting so of course it's rare you'd use all of the mechanics in the same game. GURPS gives you everything but the setting. It's a toolkit for building role playing games with very different flavors, but does this by giving you mechanics to leverage in these scenarios. Whether it's the tactical shooting or high fantasy martial arts or alien device granting super powers. There are rules and mechanics designed for it in a generic and easily expandable way.
I think we're probably in agreement and I just misread your original statement. GURPS is very much a mechanics heavy game whereas D&D married their world setting to their game mechanics and abstracted it to a degree to which they are difficult and often not worth separating. That's why it feels weird to say D&D is more mechanics based than GURPS when GURPS has mechanics for everything you could want to do regardless of setting. I'd go so far as to say GURPS is JUST mechanics, and you've got to bring everything else to make it work.
