The one I had was a complete farce
I did say with one exception. Many people do the training (full or conversion) in minimum hours so there is no scope for the 170A to be a scam, since it occupies training hours that would otherwise be required.
However recent changes mean the FTO is no longer obliged to give you the 170A
course completion certificate upon completion of the approved course (which then
enabled you to book the IRT with the CAA directly) so the old scam has been
formalised in favour of the industry.
When everything has been said and
done, gigabytes of bandwidth used on the internet talking about stuff, very
little actually changes in reality because the people are the same and their
commercial motivations are the same.
But the change is a very meaningful one. There is no longer a requirement (or perception of a requirement) for a 170A. Yes, you need a course completion certificate. You need the equivalent for just about any qualification - eg. the endorsement from an FAA CFI before you take a test.