I hate the “you don’t need more than XXX” argument. Of course you don’t need anything, but if it increases enjoyment then buy it, if not then don’t bother.
Personally, I love riding my full suspension, but my hardtail is brilliant when the conditions are less than ideal. I’m always a bit worried about using a full suss in the winter (and the hassle of cleaning it), so love having an easy to maintain hardtail that I can use. I also load it up with lights so I don’t need to faff around for evening rides, just charge them up and off I go.
Different bikes excel in different scenarios. Similarly, there’s a fun to be had by riding a less than ideal bike. As a lot of others have already said, using a less capable bike on well ridden trails can make them more fun again.