But if I remember correctly, the original idea of OncoSENS (the part of SENS addressing cancer) was something that in theory would address all cancer regardless of type.

I just reread the OncoSENS page.

The idea was to nuke the gene for telomerase from every cell in the body and also nuke a gene for alternative lengthening of telomeres (ALT).

Nuking out telomerase in every cell doesn't need further cancer research but gene therapy research. Albeit most gene therapy is about adding gene's instead of deleting them.

As far as research funding goes SENS seems to be currently funding research into ALT (http://www.sens.org/research/intramural/the-alt-mechanism). I think it's plausible that ALT research is otherwise underfunded but I don't know the details.