"Everyone" is full of crap. The compact/subcompact 9mm describes a pretty large chunk of the market. The Glock 19 is, arguably, the gun that every other semi-auto carry gun is compared against. Single stacks like the Shield are incredibly popular carry options.
Go to a rental range, shoot a bunch of stuff. Pick ONE. Get some training. Then once you know what you're actually looking for, reevaluate if you want to stick with that gun or not.
I'd at least try the Shield, XD-S, Glock 26, Glock 17 (Striker fired), Sig P229 (hammer fired), and LCR (revolver) to get an idea of what you like.
Also note that not all "full sized" 9mm have the same reach, and many of different trigger/grip/backstrap combinations to make them shorter. Unless you're REALLY tiny, a P226/P229 with an E2 grip and a short reach trigger would allow you to have a natural grip.
Agreed... the compact/subcompacts in 9mm these days are about the perfect combination of capability, carry ease and shootability (don't think that's a word). I've bounced from starting to carry with larger 357 Magnum's, small 357's, full sized 45, compact 45, dabbled with some 9mm, then to compact/subcompact 40, and finally came back to/settled on compact/subcompact 9mm's.