There's no major active user suggesting that a six pack can replace hair. That's something you're making up either from malice or from misunderstanding. I'll explain it again for the sake of the public record:
1) Some of us want to be healthy. This can be achieved by soccer, rock climbing, swimming, weight lifting, yoga, et cetera. All of these will increase life span and increase quality of life. Weight lifting is popular because it's efficient, effective, and cheap. You would have more credibility in dissing weight lifting if you were suggesting an alternative regimen that you engage in, and explained how it was superior or preferable.
2) Women go for the whole package, so try and be the best man you can. A six pack doesn't "compensate" for a bald head -- it replaces a beer belly. Nothing compensates for anything else. You are what you are. Offer the best package you can.
3) We want to like what we see in the mirror. The first thing most of us do in the morning is take a shower. It will undoubtedly improve self-esteem to be fit and look masculine and see that in the mirror.
You are in your 20s. You may not understand. I remember being in my 20s and having no health problems and having never had health problems. By the time you reach 30 or 35 if you're lucky, you'll understand the importance of fitness.
I was out last night with some people and we ended up at this couple's house. Attractive woman, early 30s. The man is around 170 cm so he's shorter in spite of living in a taller country, had a diffuse NW3 hairline so he has less hair than you, and a moderate beer belly, so he's fatter than you. He also had an engaging personality, he works as a graphic design, and entertained everybody with a lot of stories and a interesting mixed drinks.
They didn't meet off tinder, they met in real life. She didn't like him at first but likes him now. Fred may be already typing up his response "she is cheating on him with a NW1 100% certain" and you may already typing up "Fred is 100% correct as always" but here's the thing: It's obvious she genuinely likes him. There are little indicators as such. He was the focus of her gaze. She is making preparations for meeting his family, because she wants to impress. They are taking cooking classes together. She was constantly caressing him and stroking him in different ways and making out with him at random, spontaneous moments.
But he wouldn't have met her if he had wallowed in self-pity, nor would he have met her off tinder.
You should stop attacking those who take command of their life. The main effect, other than being irritating, is to make it look like you resent the reminder that you are failing to take command of your own life.
Finally, 175 cm is not short. The average height for men in Italy is 176 cm. Height is neither an advantage nor a disadvantage for you, the effect is null. It's honestly disconcerting that you've been complaining about being short for months. You're not short you're average. You don't even need to wear "elevator shoes" that will make you look like an idiot, just wear respectable dress shoes, they usually have 1 inch heels (2 cm), here's a pair of Salvatore Ferragamo, it's an Italian brand:
Here's some less formal boat shoes, for more casual days:
ETA: Damnit, that second pair looks nice !