It is as viable of a strategy as any other. People who complain about people "ratting" or being "bush wookies" crack me up... its like saying that chargin a point is a dumb way to play.. its not.. it is just the way people play. Some people are door kickers, some people want to sneak through a window, some people will camp an exit point. It all adds to the tension in a game. I think that if you are playing a game and dont like that people exit camp, like the do specifically in extraction shooters, then you might want to try a game that is more of a TDM.... Because extraction games are generally designed around chokepoints... ala EFT or Hunt to name the most dominant ones I can think of.
I have wondered if this concept of "playing the right way" stems from a generation of people who watch twitch streams. Those guys cannot really afford to play the flanking/ambush style, so people watch and think that pushing a point, or dropping into the hottest zones are the correct way to play. My old ass lacks the snap reflexes of a 15yo. I am for mid tier, or mid tier +1... So I try to play games that allow for me to push when I feel a tactical advantage, or snipe from the flanks when I dont. Which most people would never want to watch.
I mean... they dropped hte "dont be evil" tag, ages ago... which heralded the next phase of Google... "we are for sure going to be doing evil."