No, I don't think so. That's a 1980s era explanation. There are people who aren't especially attractive in all industries. Even in Hollywood, look at what Weinstein got up to, and he isn't exactly Adonis reborn.
I think the explanation is simpler: music and acting jobs are easy. Lots of people can sing, dance, semi-convincingly repeat lines written for them by other people, or even write scripts. It's just not a very skilled set of jobs. It doesn't take 5 years of study to become a great actor, people just luck into it all the time. Anywhere you get the intersection of a lot of money and easy jobs, you get jobs being parcelled out according to criteria like looks, knowing the right people, having the right parents, having the right party attitudes, or how easily they get into bed. After all, what other criteria are they going to use to differentiate between the masses of hopefuls applying for their chance at fame and fortune.
In contrast, tech is hard. It takes years of study to even get in on the bottom rung. Then it takes many more years of obsessive-level study and work to climb to the top. The difference in skill between a newbie and a master is enormous. If you're interviewing for a master software developer, and say "hey, you party much?" and they reply with something lame and boring like "no, I prefer to spend time with my wife and kids" then in a well functioning organisation they will still get the job. In quite a few other industries, if the interviewer is young that reply could easily cause you to be ranked lower than some other candidate who said "I'm always up for a good time!"