this is just not true. I just tried with one of my binaries which is 3.2G unstripped, and 150MB-ish stripped. Unstripped takes 23 seconds until the window shows up, stripped takes ~a second
There is something wacky going on with your system, or the program is written in a way that makes it traverse the debug info if it is present. What program is it?
For example I can imagine desktop operating system antivirus/integrity checks having this effect.