Second, the claims of "primitive" theory need to stop. They hold weight for an isolated single elimination game or maybe a short match. But ultimately chess is a battle of wits and logic (maybe chess-specific wits, but still). If Morphy displayed that in any era, then there is good reason to believe he may be the GOAT.
Of course, a modern grandmaster may be able to beat a fresh time-transported Morphy in an isolated or a few isolated games where the GM is working with mostly working memory and Morphy is brutely calculating, but give it a longer match (much like Fischer demanded with Karpov)... How can anyone be so sure with his savantic chess skills?
There is a fallacious tendency for people to believe that in their own "modern" time, that things are already solved to the "sixth place of decimals" and that the past is a hilarious primitive world of wacky superstition, illogic, and idiocy, then an Einstein comes and introduces relativity, and the joke is on them.
Today's chess theory is insanely primitive compared to what it will be in 50 years. But a brilliant logician, memorizer, and pattern-recognizer will always be so, and one who can show that s/he can do it better-- nay, overwhelmingly crushingly better-- than the rest has to be in the GOAT discussion.
Actually I am not trying to change your opinion Lady. As far as your projecting statement goes, whatever. However I am not saying his biographer is even wrong, but it was definitely written the way he saw it.
I also believe I know a little bit about history, family matters, and customs as well. I also know a little about our medical history.