I had a friend in grad school who entered the Ph.D. program after spending four years in industry. He was very passionate about his research area, persistent, a fountain of ideas, and wonderful to talk with. He ended up winning the ACM doctoral dissertation award for his thesis, did research and teaching at a university, and has since returned to industry.

This may be the exception that proves the rule. However I just wanted to point out that there is at least one person who did catch up to become a research scientist, however rare that career path might be.