While I certain to NOT agree with cutting dashes, I would agree that the matter is an individual decision. That decision should be based of full knowledge of the implications. Anyone who has ever tried to repair a "hacked" dash knows that it is a huge job. I'm not talking about a plastic "repair" panel but a quality repair of the dash metal. Having actually done this repair, I feel that I am in position to make an informed judgement.
Having been in the hobby for MANY years, I have seen this "problem" handled many different ways. Suppose "Stanger X" installs a "Mega-Blaster III" by taking a reciprocating saw to his dash.

Fast-forward a few months and the "Blaster" croaks, off warrantee of course. "Stanger" takes the "Blaster" in for repair only to find that it costs more to fix it than it is worth (a common problem). Since the "saw job" on the dash was "custom-cut", nothing else will fit. The hole is TOO LARGE! What does "Stanger X" do now? Hmmmmmm?
And so, on I could go with stories based on how I've seen people deal with the stereo question. Carrying a "boom box" on the rear seat works for some. Using stock, but internally modied radio head works for others. Be creative and think "out of the box" people!