Not enough for concern.
Floor joist crown.
They sure don t build them like they used to.
I have full access under the joist a 2x12 with a full basement.
The joist on the other side of the crowned joist was properly level meaning it was in plane with the end joist.
I am retiling bathroom floor and have a very noticable crown on one joist the other joists all appear level.
Long joist is applied.
The joists that is cut will stay crowned unless acted upon by an outside force though it may drop a teensy bit.
This is a crown.
If the crown is less than about 3 8 you can just sand it down with a belt sander.
Actually the 2x4s could be added after the notch is made and the glue and 8 ft.
Then use screws to draw down the crown then set the splicing joist in tight.
Joists that have severe crowns need to be set aside or some of the crown needs to be trimmed off so the floor remains fairly flat once covered with plywood or oriented strand board.
Between it and the end joist just 12 inches away there was a 5 8 inch drop.
It appears the previous tiler tried to deal with the crown by putting a grout line directly on joist and tilting the tile slightly but it is still quite noticeable.
Take a look in the crawl space to see if anything is forcing the joist up beam stub wall.