It's a good point, but in practice it depends on how easy those customizations are to implement / maintain, and how much money and effort you save. At some point the compute cost can disrupt even the nicest scale story.
I think the path forward is that websites offer one path for humans, and another for scrapers. But the huge catch is the path for scrapers must be _genuinely_ and _reliably_ the more economical and scalable path (either through something like PoW arms races, or through fear of litigation). Otherwise they will continue to ignore instructions and intrude on the human path.
The temptation to offer different / inferior / limited content to scrapers will be too strong, so such solutions are doomed to fail.
This would likely work as "Cloudflare SideChannel", a (hypothetical) Cloudflare product that would let scrapers download the pages that humans actually visit, as they are added to the CF cache. It wouldn't work for the non-Cloudflare part of the internet where humans connect directly to the servers that have their content.
The moment we establish a standard for offering a "optimized for scrapers" version of a site, people who do not want to be scraped will weaponise that to serve junk to scrapers... and scrapers will subsequently refuse to use it.
Largely because they're residential botnets in places like Brazil (a real example from one of my sites that was crawled to near-destruction). Someone could probably do something about this, but it's out of reach for individual site owners.
How good are you personally at iteratively and sequentially jumping through the legal systems of dozens of countries over the course of years, interleaved with genuinely difficult technical investigation, to unmask successive onion-layers of identity in order to unmask one offender?
Oh, and it also only takes a few minutes to reconfigure everything and invalidate those years of legal and investigatory work.
I think the path forward is that websites offer one path for humans, and another for scrapers. But the huge catch is the path for scrapers must be _genuinely_ and _reliably_ the more economical and scalable path (either through something like PoW arms races, or through fear of litigation). Otherwise they will continue to ignore instructions and intrude on the human path.