To me the fun part of the game is hanging out with mates once a week and trying to keep them semi on track- herding cats is how I describe tryig to get them to work cohesively or buy into an adventure but they come back week after week. It's not the rules per se (5e is in many ways our edition of least complaints and we do all agree that desite the issues we have with aspects of it overalll it works and makes for an entertaning gaems so we stick with it). Each of my players enjoy different aspects of the game- some like rping, others the combat element, thankfully noone are into building uber characters, others the intellectual challenge of outwtting the dm and finding creative solitoons to problems. But when they come together as a group the magic that happens around the table is what brings me back each week for more- so I guess its the people not ther rules that make D&D fun for me.
As a DM my most rewarding conversations go something like this:
Player: Can I do this...?
DM: Yes
PlAYER: What about this?
DM: Yes
Player: So if I do this what is likely to happen to/what will x do if...?
DM: Well this is likely to be the result.
[A few more similar questions, the dm not sure where the player is leading but willing to play along, whilst trying to see the catch).
Player: [Once satisfied they have the DM where they want them]: Okay,so if I do this.... then this will happen... and then this...
DM: Now getting increasingly paranoid and knowing the player is up to something, frantically trying to see where this line of questioning is leading when...
Player: So if I tell X this, do this, then this will happen, correct?
DM: [now very, very worried...] Correct
Player: Satsfied he has the DM where he wants him the player puts his entire hand on the table]. Great I do X..Y..
DM: Arrgghhhh!
Outplayed by the players I bluff and bluster about abuse of the rules fully knowing I've been lead when they wanted me and despite my best efforts didn't see something in the set up coming and was blindsided (while inside I am going f$#ken A, that wa awesome) that's what l love about this game!
Being outwitted by my players is the fun part of the game for me, as I know then I've done my job. They've taken the mechanical aspects of the game + their own intellectual creativity to push the game (or a particular challenge) in ways I'd not dreamed of. D&D has always been a game of the imagination, love nothing more than seeing it being used.
Stormdale