...Earlier he and some others went forward trying to support Haeckel's ideas about embryos. ..
Uh, not exactly.
Js1138 and I posted data that showed that Ernst Haeckel's theory was based on observation (virtually identical-looking vertebrate embryos, laryngeal nerve). Ichneumon posted more details about his theory and the appearance of his drawings in textbooks.
But no-one has supported his theories here; in fact, no biologist has supported them in the last 100-odd years
Yes, although perhaps less than 100.
That's what I found so strange about certain people here stating and arguing/defending "ontogeny recapitulates phylogeny".