When dismounting from a minecart or using activator rails in the North/West directions you get ejected forward; however, in the South/East directions you get ejected backwards (as I think should be the case). See the green spaces in the default case screenshot for where you get ejected currently.

There is further inconsistencies to which side you get ejected on between the N/W and S/E directions. They should probably all be made consistent (red wool in default case screenshot if South is the primary/correct one).

Things get further inconsistent with walls in the way which causes issues like MC-1489 (I've teleported through glass panes this way), where in some cases you eject on the track (which is good), but not always (especially in the north case as in the 'blocked case' screenshot). Not sure if this means it is also related to MC-36482. It seems like if you can't eject off the track, you should eject on the track behind the activator rail.

North is up in all screenshots - attached my test world as well (which shows minecart ejection is the same as activators and that the same issue occurs if the activator is powered by detection rail or not).