It's 100% untrue. Men are beautiful. You are beautiful. Believe in yourself and remember that the most attractive thing in the world is a kind heart and that starts with being kind to yourself.
Don't let the world make you feel ugly, they're just trying to sell you shit.
If you know how to sew, taking in clothing to better fit your form can seriously make a world of a difference you won't even believe, and it costs a grand total of about $0.47 cents. If you don't know how to sew, you can learn hwo to sew by hand in probably an hour, and its a great repetative monotonous meditative thing if you're into that sort of stuff. Sewing by machine is quite a bit harder, but 20x faster or so.
I re-sew my cuff buttons to fit my wrists better cos it's beyond easy, but with stuff like putting darts in I always feel like I would do it wrong. Having a tailor do it also gives that confidence that a second person (who knows what they're doing) thinks the proportions etc are right. But I 100% agree that getting stuff tailored was like magical witchcraft for making everything look a million times better, and even the cost of getting a professional to do it is pretty low compared to the cost of new clothes.