I've played every NMS expedition and while there have always been a problem Communication Stations, it wasn't until this latest expedition that I felt like trolling was getting worse.
On the first day of the expedition, I claimed a spot at the 2nd rendezvous system around some Runaway Mould, built a small base, and uploaded it. I slowly kept adding to the base over time, especially once I completed the expedition. So far I've had at least 8 different people build on top of it, which means I have to report their bases just so I can walk around my own. While I've had some people build close to my base, I have never had anyone literally build on the same spot, much less multiple people.
It stinks that Hello Games isn't doing a better job of making sure bases can't overlap, but it stinks even more that people take advantage of it.
It's probably made even more of a problem for the Normandy expedition because of the incentive to disconnect and play offline. Trying to find uncharted systems is a chore if you don't.
So let's say you just forgot to reconnect before creating your base, of course the game won't find any overlap.
The game should check overlapping again for upload, not just creation.