If you love the someone you're with, you don't care about other opportunities. What would be the point? Some special organs that another person doesn't have? Keeping score of how many times you've got laid?
On the other hand, if you don't love someone, then it doesn't really matter if you get other opportunities - they're just empty fun for an hour or so but feeling empty afterwards.
Sure, it's cool to be a "player" for a little while in your late teens/early 20s, but it gets boring soon, just as the fun with alcohol and partying and many other things. Most of the people you know that 'did' go to parties and such, are dead bored of them at this age.
Also, is all this a real desire - things you really want to do today, or merely a response to a fear of having missed out? These two cases are not the same.
Lastly, you're just about to turn 30. You are still young, and can do anything you like to turn your life around. Heck, even someone at 40 or 50 could...
As for "transitioning to the industry" it's probably not a bad idea. Modern academia sucks, and unless you've made it somehow, it can be even more work and less pay than the industry. Heck, people make money even as nomads working remotely (and I'm not talking nomads making money by selling the nomad lifestyle: I mean people really working remotely from some city in Thailand and co, without vlogging about it). Plus, the modern industry (if we're talking IT) is hiring...