Nah, I don't agree with that at all, especially concerning The Wall. Now, I'll grant that things got rather iffy with the band as a whole after Animals, but The Wall is still solidly a shared effort between Waters and Gilmour. It could be argued that Comfortably Numb is the most famous PF tune of all time. With two of Gilmour's most beautiful solos. IIRC, either Mason or Wright had essentially left the band at the time, so that helps your argument. But, as with the "there was no real Pink Floyd after Barrett left" crowd, the arguments of a fragmented timeline just don't work for me. Pink Floyd started with Pipers and ended with Cut.
Period.
Now, I'll grant you Cut essentially was a solo Waters album, but it was still Pink Floyd, for better or worse. No Wright, hardly any Mason (IIRC), many of the guitar parts played by musicians other than Gilmour (who only sang on Not Now John), etc...
At the end of the day, I fully understand what you're saying, I just disagree.
Or as Dave belted out at the end, "Fuck all that, we've got to get on with these!!!"