This is sort of over stated generally.

In Australia where North is “optimal”, even South facing panels produce only 20-30% less and East/West about 15%. It does vary a bit by latitude but it’s not at all pointless to install them in other orientations in many places. I have not done the math to see how much of the world this extends to, but it applies to a fairly large chunk of Australia. Source: https://www.solarquotes.com.au/panels/direction/

Tesla’s system also had non solar tiles so you could just skip the panels in whichever parts you wanted.

Roof construction is quite different here to the US though. We never have the plywood layer, it’s either ceramic tile or Colorbond steel directly onto usually wooden sometimes steel beams.