the fact that I subsequently connect to another place over HTTP or some other protocol is distinct from telling a DNS authority who is asking a question about a domain name: the article implies "its the same leakage" but it isn't: different people get told.
I don't have good sense of this, but people I trust say a surprisingly small collection of information identifies you to a specific level. same /24 is only 255 people if there isn't a CGN. More to the point, if your /24 identifies your economy, you're now subject to IPR limits and can be told different things.
So some ECS objection is rooted in opposition to regional IPR. Netflix. Sub-optimal CDN delivery (to one person) is wall avoidance (to another)