Len had significant time and topic correlations to many/basically all iirc of the feeder research and projects that clearly fed into BTC. SN also went offline around the time Len passed. Those two factors plus the related details sealed it for me.
Edit - like if I was known to research under Szabo and Finney (iirc) right around the same time BTC launched, was known to advocate to peers to launch controversial open source under pseudonyms, and so on, I’d probably wrap my public persona under “BTC sucks” and my SN persona under “idk linux well,” and so on. Seems an obvious step to take.