Neither have I [been on a cruise ship] and I have zero interest of ever doing so. The things you do on these expensive cruise ships you can also easily do on a staycation at a local hotel or resort.
Cruise ships are for some people, not others. Like many things in life, they’re a mix of many elements both good & bad; you have to be able to filter just what it is you’ll enjoy. I use the same philosophy regarding gay clubs & bars. They are what you choose to make of them, not what they make of you.
Regarding cost, cruises aren’t really that expensive. In fact, to get the same service & features in a conventional hotel or resort you’d likely spend much more.
Those ships really are floating palaces, if a trifle gaudy for my tastes. But you get an incredible variety of activities, with shows onboard (even an ice show on one we did, along with a big stage show), lots of food to eat that was pretty good, of course bars everywhere, casinos (that we avoid), excellent attentive staff, and just the fun & novelty of being at sea with the ocean outside your state room balcony. But honestly, little time is spent in our suite, too busy elsewhere.
Plus there’s 1 or more port calls. The challenge is to decide which of nearly 200 available onshore activites to take, from snorkeling, swimming with dophins, parasailing, horse or ATV rides through jungle (on Caribbean destinations), visiting ancient ruins & local attractions, water & jet skiing, boat sightseeing (some glass bottom), shopping excursions, some people just go to a golf course, it’s impossible to do it all in the day or 2 you’re there.
As for the crowds, we never encountered that problem, despite the huge ship size and number of passengers. It’s incredibly well organized. Even boarding and then returning was fairly quick, actually faster than some airports, despite customs. (We use Port Everglades in Fort Lauderdale, and prefer Royal Caribbean cruises).
But we are cognizant of the highly contagious diseases that sometimes strike these big ships. There are hand sanitizer stations everywhere, and we use them (I normally don’t elsewhere). We’ve never gotten sick, nor were there any illness issues on our cruises. Nevertheless that’s a consideration in deciding to cruise.