[eaton]

> if you’re planning to be a top 10 site on the internet, you’ll need a custom stack

To be fair, that's the case with pretty much any CMS. Even if they start with a stock system, by the time they actually hit top 100/1000 (let alone 10) there's a lot of custom work to be done.

And realistically, a "top 100/1000 site" is almost always going to have a cloud of other sub-sites and related properties. The corporate site, intranet/HR, jobs and recruiting, press center... The penumbra of "Oh, yeah, we need one of those... but it would be ridiculous to build it from scratch" sites for a large organization can be pretty large indeed.