One caution here; at least with AZ, apparent rate of clots varied dramatically by country, and rates generally went up once people knew what they were looking for. It's plausible that a lot of early ones were missed entirely or misattributed.
That's 6 unusual/dangerous cerebral clots per 7 million doses, not all blood clots. There were 50% more clots of any types in the vaccine trials of 20k people [0] (15 blood clots in vaccinated group versus 10 in the placebo group).
Ah yes, that is true! This site is based on AZ, but you're right it might be a different story with J+J. I wonder if as well, they'll get better at spotting the blood clots and treating which could also be happening - but that's just conjecture / hopeful thinking at this point.
