Many years ago, I experimented with Sierra 125gr, and Hornady 130gr in a .30-06. I even shot a few deer with the 125. They are both designed as varmint bullets, and thus are very fragile. On rib shots, theyseemed to workfine, although none exited.But, on a shot that hits solid bone, one had better be ready to shoot again.
Incidentally, although they start out faster than a 150gr, the sectional density of the lighter bullets is so poor, that at longer ranges, the trajectory was much higher--ie: they dropped more.
Because the negatives (and potential negatives) far outweigh the positives, I see absolutely nouse for a .30-06 bullet of less than 150 grains for deer.