This is broadly how Intel memory segments were supposed to work. The 8086 did not check bounds, so nobody bothered using them, and when the 80286 came out that

This is broadly how Intel memory segments were supposed to work. The 8086 did not check bounds, so nobody bothered using them, and when the 80286 came out that could check, everybody disabled that feature and used it as a faster 8086. Probably too many key programs played too many tricks assuming a flat memory model that this was never going to fly.