I'm also not sure that what we are seeing is linked to the the ETF. However my opinion is based on a simpler notion. Recently when Bitcoin went up OR down in value it sucked in market value from ALL the altcoins. Bitcoin market value domination is now at 51% up from 50% two days ago and up from 39% a month ago. The speed of vaccuuming is increasing.

This is all despite altchain projects actually coming to fruition, goals being realised and increasing presence of mainstreet in cryptospace. Similar shakedowns occurred in internet 1.0 and 2.0.