End game is kind of then you reach max level and is also done with questing, clasic WOW is an good example.
Its not the same for ESO, yes gear cap is cp160 and this make vet dungeons relevant.
You can also say its vet trials and pvp, however the vet dungeon progression is also long.
On the other hand you are not done with quests even if only leveled by quests and can continue with them.
Or you can do it all,
Of course, it required me to level my crafter up to level 50 CP 160+ to be able to solo a lot of stuff, travel all over Tamriel to gather enough skill points to feed the crafting skill lines, and to gather enough resources to be ableto craft my own furniture too. Joining a nice large social guild helped a lot with obtaining many recipes and clearing certain locations too hard to solo for me. I also did spend some money in the Crown Store, I even bought some Crown Crates, because the seasons offered items I wanted, such as costumes and adornments.
I find great fun and joy in furnishing my houses, creating interesting looks for my characters and then coming up with stories for them, and living these stories myself. Having fun in my opinion is the ultimate goal and endgame in ESO for many of us.