When minecart  track is placed going uphill going up by 1 block at a time so the track is flat at a 45 degree angle:

If you stand one on piece of track and look straight ahead at the track in front  of you, you break the block the track is placed on and not the track itself.

Basically, the hitbox of track going uphill is the same as the hit box of a half slab. This is wrong (well I think it’s wrong) because you can break blocks “through” the track.