You never know! They won't be saved, so finding a running one in 30 years. I mean, people collect Dysons, they were mass produced plastic junk once! Your Hoover 725, in the 50's it would have been rag and bone man fodder for most people...
Tenuous I know, and I'm not keeping one to find out, but someone may be as excited about one as the current crop of young collectors are about Henry vacs and shark stick vacs