Of course you need to have more than one thing going for you (unless your in the very top tier, a rockstar can carry himself on his guitar). Who ever says otherwise?
That doesn't mean lifting isn't important, and I wouldn't say its "icing on the cake either", like your argument is pretty bad:
A 6'4", broad-shouldered guy with a decent face who has never touched a weight in his life will be considerably more attractive to women than a 5'6" narrow-shouldered guy is muscular and with a six-pack.
5"6 is the 13th percentile, 6'4 is the 99th percentile. That is like saying "Height is like the icing on the cake, a man who makes will $300000/year be more successful with woman than one who makes $12000 (13th percentile). Well yeah, if you make 12000/year, your height probably isn't very important, but thats not because height isn't important, its because your fucking poor.
Similarly, that a 6'4 guy might be better off than 5'6" who lifts weights, but thats not because lifting isn't important, its cause 5'6 is really short so its hard for muscles to compensate for that.
Most importantly, what you seem to be missing is you can't (yet) change your genetics. So yeah, you may never be as attractive as the 6'4 guy with the chiseled face, but you'll be more attractive than the 5'6 guy who doesn't lift.
Finally, who cares if the 6'4 guy is more attractive? He is literally 1 in 100. Hes not your competition. Most other men are closer to you in height, and the closer they are to you, the easier it is for you to stand out in other ways.
If you weren't having luck with women before, getting ripped won't help improve your situation.
Do you really think that given two guys who otherwise identical, the one who is ripped won't be more successful?
Everybody is doing it... In the past before the Internet, maybe a built physique was something of a novelty.
lol No. If anything its the other way around. Young men in the past were far fitter than they are today. I can't find the stats for adults in their 20s, but 15 year old boys weighted ~130lb on average in the 60s and ~150lb on average in 02.