I have no idea why people say this. Airline baggage handling is incredibly robust and, if for whatever reason your baggage doesn't pop out of the carousel when you arrive, they deliver it to your hotel or office or wherever ASAP, usually the next day. Airport backends aren't dark warrens full of hiding places, they're well lit spaces. Suitcases don't just 'disappear' any more.
I've flown on at least 300 two-hop flights and never had a baggage issue in either the US hubs, the ME hubs or HK/SG hubs.
Your luggage often shows up 3 or 5 days later, not the next day. Which can do a lot to ruin your vacation, especially since you might be traveling on immediately from the city you flew into, whether by car or train or boat or whatever.
And suitcases absolutely still do disappear. Happened to a family member last month. All it takes is for the label to be torn off, or somebody at baggage claim to accidentally take your bag while you're still going through immigration.
Or it just gets put somewhere and forgotten about. Another family member's suitcase got returned... five months later. Apparently it got locked in some room that they never access.
I'm happy you've been so lucky, but don't assume everyone is.
I don't think your experience is common, at least not post COVID.
Just this year, flying direct to Hawaii, checked a bag because of baby gear. United cancelled the flight and due to staffing, would not/could not return checked bags (so I could fly Alaska) for almost 24 hours.
The bags has not left SFO. They literally took a day to move them from the back to the front.
I only made my new flight by finding the right person who was willing to task someone to go pull my bag early.
I rarely check luggage and delayed luggage for various reasons—or no apparent reason at all—is not at all an unusual occurrence in my experience. And there’s no guarantee your luggage will be able to just catch up with you at some random location in a day or two.
It’s better than it used to be but I have routinely had luggage miss connections or had checked luggage be an issue when rebooking flights because of weather etc.
I've flown on at least 300 two-hop flights and never had a baggage issue in either the US hubs, the ME hubs or HK/SG hubs.