I've owned a couple of Glock 33's in my time, which is Glock's itty-bitty subcompact in .357SIG. They were a hoot to shoot: Lots of flashenbangy with target ammo and they'd throw the brass into the next county.
Like half the .357SIG shooters on the internet, I'd crow about how "flat-shooting" the round was...
...which, in retrospect, made me look a little dumb.
See, at the time, I did almost all my shooting at an indoor range, and at seven yards, all pistol bullets shoot flat. At 21 feet, there just is not one lick of difference in trajectory between any two handgun rounds. At 25 yards, there's hardly any, and even 'way out at a hundred, beyond where most people will ever shoot a handgun, there's only about 7 or 8 inches of difference between the trajectories of a lumbering 230gr .45ACP and a zippy 125gr .357 Magnum.
This is because trajectory is mostly affected by speed¹. Bullets start falling at 32ft/sec² the instant they leave the barrel; the faster they're going, the more ground they'll cover before they fall. And pretty much all handgun rounds are travelling about the same speed, which is "slow", at least compared to rifle rounds. Seriously. There is a larger velocity spread between the slowest and fastest commercial .30-'06 loads than there is between a "slow" handgun round and a "fast" one¹, and the "lumbering, rainbow-trajectoried" .45-70 will outrun your "zippy" 5.7x28 wonderpellet.
Differences in handgun velocities and the resultant trajectories might be important if you're trying to whack a coyote at 100+ yards in a soybean field, but if you're only shooting at 7 yards at the indoor range, don't pop off a magazine and then turn to your buddy and natter about how "flat shooting" your favorite heater is, okay? It's like walking up to a painting and saying "Hmmm... Interesting use of negative space!" or swirling a mouthful of wine around and saying "Pretentious, yet understated!"; it makes you look kinda goofy.
¹ And velocity is affected by ballistic coefficient, and... but that's a whole 'nother kettle of fish.
²The velocity spread between a "slow" handgun bullet at ~900fps and a "fast" one at ~1400fps is less than the difference between a 125gr .30-'06 at 3100fps and a 220gr .30-'06 at 2400fps.