Super late to this but they mention element overlap in SVG making thinks like drag & drop hard. That's their "interactivity" gripe, and the one that for me carried the most weight.

I'd be very interested to get more discussion on this specific issue, of handling mouse events well in SVG.

The particular example felt contrived, in that I might just apply a class HasPointerEvents to every element and change the pointer events off for everyone except the drag & the dropped element. But I suspect there may be some other real mouse handling topics in SVG that really are interesting & challenging, & would love some discussion on that. Kind of iwld that the internet doesn't have a ton of obvious forums to go hash out tech topics like this... Post a random question/challenge to stackoverflow & cross your fingers.