What do you actually enjoy about heavy / expert board games?

I’ve been getting more and more into modern board games lately, but there’s one thing I still struggle to understand: what exactly makes heavy / expert games so enjoyable for people who love them?
I’m thinking about games like Ark Nova, Terraforming Mars, Dune: Imperium, Brass: Birmingham, etc.

Personally, I’ve tried getting into heavier games several times, but I’ve never really managed to enjoy them. And honestly, it frustrates me a little, because I feel like I might be missing out on an important part of the hobby.

My main issue is the ratio between time invested in learning the rules and the strategic depth / enjoyment I get from the actual game.
For example, I can spend an hour (or more) learning a heavy game, only to discover that once I understand the rules, the actual strategic decision space doesn’t feel dramatically more interesting to me than in a much lighter game. Sometimes it even feels like I’m spending more time managing rules, exceptions and mechanisms than actually making meaningful decisions. To have an idea, the boardgames I play and enjoy the most currently are Heat, Clank Catacombs, Sky Team, Everdell, The Search for Planet X and Carcassonne.

That’s probably partly a matter of personal preference, but I’m wondering whether I’m looking at heavy games the wrong way.
For those of you who genuinely love expert / heavy games:
What is the specific pleasure you get from them?
And more importantly: do you think someone who doesn’t enjoy heavy games is actually missing something fundamental, or is it perfectly reasonable to get the same kind of strategic satisfaction from lighter / medium-weight games?

I’m particularly curious about people who enjoy both light/medium games and very heavy games. What does a game like Brass: Birmingham or Ark Nova give you that something like Heat, Everdell, Clank! or The Search for Planet X doesn’t?
I’m not trying to argue that heavy games are overrated. I genuinely want to understand the appeal from the perspective of people who love them, because I’d like to know whether there’s a part of the hobby I’m simply not appreciating yet.

Thanks in advance for your perspectives !!