That’s news to me on the godfather front, but the restoration really did the best with what they could work with. I have the reissue early 90s open matte LDs and the restoration bds. I threw out the original DVDs which were quite awful, and I had the restoration DVDs but they never had differences that I noticed like the ones pictured on that website.
The only real evidence we can get that would tell us anything would be dye transfer prints from that era which should exist for part one and part two, as part two was the last American IB run done in the 70s.
That said IMO I don’t think the restorations are off at all considering the mammoth amount of work they had to do. The only downside is the mono original audio is relegated to a lossy track.