I think, the developers have already relented a lot. It is much better than in Photos on Sierra, when we could not block memories at all.
At least we can now block the memories of specific places and faces. We can stop photos from confronting us with photos of places we do not want to be reminded of or with photos of the persons we cannot stand at the moment.
It took me ten minutes to delete all memories and I keep blocking new memories that pop up. I have not been presented with a new memory in weeks.
But Apple has still a long way to go, to make it user friendly, you are right.
Send feedback, as suggested by leroydouglas.
The feedback form for Photos for Mac is here: Feedback - Photos - Apple
And for good measure, send feedback to the iOS team too: Photos for iOS - Feedback - Apple
The syncing of memories across devices makes the blocking difficult.