Speakers have been successfully used full range for decades, long before "subwoofers" became a household word. From small table radios with 3" drivers to JBLs and Klipschs with 12" and 15" woofers, the majority of which I am sure survived for years without destruction or producing audible sonic aberrations when used within their design envelope, and I am completely comfortable posting my own opinions on them, along with facts based on actual personal experience.
Subs aren't perfect either, and produce their own set of distortions when THEY are pushed too hard.
BTW I haven't noticed anyone here, including myself, to be FORCING anyone to set their system up in XYZ manner. As far as my own posts, they are liberally sprinkled with lots of "IMO", "I think.....", "to my ears......", "seems to be....." etc etc, giving the reader ample warning that any advice I write is not written in stone and they are on their own when it comes to their own system's configuration i.e. I won't be responsible for anything they do to their own system based on my advice. Plus I never EVER said anywhere on this forum I was a professional audio set-up person or that I was giving out advice that will always 100% work for other people's systems. Lastly, I've seen plenty of truly ignorant advice written here - with NO indication it was an opinion or even a guess - advice that sometimes I believe WOULD cause physical damage to equipment if it was actually implemented.
And: the instructions in the manual for a piece of audio equipment is what someone should always abide by. So if some anonymous person on the internet gives advice that conflicts with the instructions that are written in that manual, ignore that person!