Between the two, I’ve always found the thinner profile of the 1911 easier to conceal and just feel better to carry, for me.
That said both are too heavy for me these days.
I carry a 1911. An Ed Brown Executive Carry, but soon will be switching to a Wilson CQB Compact.
If the weight of a 1911 is a problem, it could actually be your belt and holster choice that's the issue, rather than the gun. How much weight do those extra rounds in the mag of a Glock add?
And I have never thought of a Glock as less bulky than a 1911.
Belt can only do so much, and a wide holster does help, but that presents further concealment issues with a large footprint gun. Leather is nice but gets wet if you get hot and sweaty like I do, got tired of needing two IWB leather holsters to rotate in the summer.
For reference in weight, fully loaded according to my scale.
Dan Wesson VBob is 43.4 oz (2 lb 11.2 oz)
Glock 19, with Holosun is 32 oz (2 lb)
That’s nearly a pound lighter on the belt, which is significant to me and especially my back at the end of the day carrying IWB.
If one needs a .45, something like the Glock 30 or HK45C are about the same weight and still hold 8-10 .45.
The Glock 21 is about the same size as the commander 1911 (with a thicker grip) but holds 13 and weighs 40 oz, heavy for me but still almost a quarter pound lighter than a commander 1911 and shoots, IMO, much softer.
When I had aluminum framed 1911s they typically were around 36oz loaded, and that’s nice in 9mm for sure, but I never liked their recoil in .45, too slow on follow up shots.