I've experienced the "filter" issue with online dating, but my conclusions are entirely different.
I really don't mind it, in fact I appreciate it.
Anyone who would filter me out over something as shallow as height would undoubtedly be an extraordinarily poor match for me.
I prefer quality over quantity.
As to the "die alone" thing - that seems a bit grim.
I'm 46, since age 14 when I actively started dating the longest I've been single was for about 3 months after a bad break-up, and that was by choice.
Sure, when you don't have a height advantage you have to make it up in other ways - personality, fitness level, professional success, etc...
In general, I think my relatively modest stature has been a benefit to me. It forced me to be a better person, and to focus on qualities that matter, rather than superficial things.