I think a lot of people mean "Wedding DJ" or "Radio DJ".
However there is a whole small subculture around this. A friend would go hunting for records to sample in Charity shops for old vinyls (this was pre-ebay). This apparently is known a "Digging" and lot of Music Producers, DJs etc would do this to find samples for their sets/albums.
Discussions about "DJs" are difficult because there's a WIDE range of skills behind what we call a DJ.
Yes, some have zero skill and will basically just show up with a pre-determined Spotify playlist. They won't even have mixing/transitions between songs.
Some are in the middle and will be able to do basic transitions between songs (ie, just simple beat matching) and know how to carry a vibe.
At the far end of the spectrum are actual composers that are effectively making new mixes of songs on the fly.
And so you have the problem where someone says "Being a DJ takes a lot of skill" because they're thinking of the last category, while the person hearing that message replies with "How does it take skill to just press Play?" because they're thinking of the first.