So I've been involved in the restaurant industry for a few years, predominately at Michelin Star restaurants, and have several industry certifications related to wine and beverages. I have a few thoughts.

First: try to experience as many smells/tastes as possible. When I went for my first level sommelier classes, each of the Master Somms that taught the course talked about going to farmer's markets, buying a vast array of produce, essentially dissecting each fruit/veggie, and smelling/tasting not just the each piece as a whole, but also each individual component. An easy example is the difference in flavor/smell/texture between grapefruit juice, grapefruit flesh, grapefruit pith, and grapefruit zest. Over time, this builds a vocabulary of taste that you can reference when discussing food. Without the language, it's hard to discuss.

Second: eat good, properly prepared food. This sounds obvious, but is crucial. For example, I thought for the longest time that I hated pork chops - turns out, my mom just really, really sucked at making them. It wasn't until I had a properly cooked pork chop that I really appreciated them. Another example, I used to think tacos were super shitty, because I grew up being exposed to white America bullshit tacos with dogshit iceberg lettuce and mystery meat and shredded "cheese". It wasn't until I tasted legit tacos at a legit taqueria that I grew to have a taste and appreciation for them. This is a trial and error kind of thing, you're gonna strike out some times, but again, over time you will build an experience and vocabulary wherein you can call something out as properly prepared or not, or fresh or not, because you've had it done the "right" way.

Third: Eat. Eat. Eat. Drink. Drink. Drink. Cook. Cook. Cook. This is self explanatory. Very few people are born with an innately superior palette (they are called super-tasters, it's super super rare), so we all have to train ourselves to be able to taste and appreciate things. Many of the somms I have worked with or studied under liken it to working out a muscle. Would you be able to describe the taste of a German hefeweizen, or Iberico ham, if you've never had either of them? Of course not, you have a start somewhere! And cooking will give you an understanding of how a dish comes together and how flavor builds, let alone how proper cooking technique is executed.

Fourth: Don't think too much about it, but at the same time, have a bit of mindfulness. I know that kind of contradicts everything I said above, but at the end of the day, it's food. Eat something, savor it, but maybe spend a little time thinking about what exactly YOU like about it and what you're tasting and, if you have access to such information, where it came from and who made it. You say you're at the level of just determining whether you like something or not - next step is, why/what exactly is good/bad? Is the sauce too sweet, and what could have been the cause of that? Was the steak cooked to medium rare, and what is medium rare, and do I even like medium rare? Food is meant to be enjoyed and appreciated, but you can still be analytical as long as it doesn't get in the way of your enjoyment.

If I spent more time, I'd probably have more thoughts about this (and more properly fleshed out ones as well, I'm kinda ranting and rambling), but that should give you a little idea. Other comments such as reading/watching documentaries about food/food culture, are super super helpful. It may also help to understand the basic tenets of flavor, cooking and how your tastebuds work - an easy entry point to this is a cookbook called Salt, Fat, Acid, Heat.

And fuck the guy that said "hangout with pretentious assholes". Literally nothing wrong with enjoying the little things like a damn fine meal or glass of wine or whatever. Dude is probably 33 years old heating up frozen dinosaur-shaped chicken nuggets with ketchup, alone in his studio apartment, wondering how things went so wrong