Pretty much. The grind to max manifest is a long process (unless space magic is applied) and is a great way to get frustrated and burned out. Play for fun and treat getting URs as a side bonus.
Agree fully, so many seem to consider just getting a maxed manifest to be the ultimate goal of this game. There is so much variety in everything else the game have to offer. The URs are nice but it's not really needed to have them all at X to enjoy them.
The most fun I had in this game was when I didn't have a maxed manifest, each time I unlocked a new UR card it feelt like a small step of progress and by taking the time to fully max it out I learned a lot about the game.
The first gold and platinum games I did when I was very far from a maxed manifest are the best memories I have from this game.