A bit late seeing this thread, but I do have a wonderful mango tree that's been here since we bought this house 15 years ago. I've had to prune it quite a lot lately, the last two years in the fall, especially broken branches after Hurricane Ian thrashed it. But it has the best crop of mangoes in many years this year.
I also have a lychee tree, which I planted the year we moved here as well.
Only one year have I had any lychee to harvest. Apparently they bear heavily in alternate years - one year lots, next year hardly any - and it seems that the birds and squirrels like the fruit while it's still green, so unless I remember to set out my motion-detector sprinkler at the right time, the fruit is all gone before I ever see it. Very frustrating, because I just love lychee fruit. No fruit again this year because we were away for 2 weeks at the critical time . . . ARgghh.
What I came here to say is, planting fruit trees is like setting out the "Welcome" mat for every bird and critter in your vicinity. Birds, raccoons, rats, squirrels and yes, random people as well will steal your fruit (we caught a neighbor on our doorbell cam). The squirrels I've sort of figured out, since they're active only in the daytime - I just set my watch and walk out every hour or so with the hose, and 'flush' them out of the tree. Pretty soon they hear me coming and run. But the nocturnal visitors, raccoons and rats are much harder to discourage. I lose a lot of fruit each year. Again, the motion-detector sprinkler is the best deterrent, because it can "see" at night. But I only have one, and the motion of the wind moving the foliage sets it off so it uses a lot of water under the tree.