Not even close. The blog post was 2017.
Actually, I stand corrected, after double checking, Cloudflare were using Silver. Entry level data centre chips, instead of small business chips. Still not the kind of chips you'd buy for high performance infrastructure, and not intended to be used for such.
Xeon Silver 4116s hit the market at $1,002.00. The Golds were $1,221.00. The performance differences are quite significant. For something that'll be in service for ~3-5 years, $200 is absolutely trivial by way of a per-chip increase. It's firmly in the "false economy" territory to be skimping on your chip costs. It's a bit more understandable in smaller businesses, but you just don't do it when you're operating at scale.
Also remember: at the scales that Cloudflare are purchasing at, they won't be paying RRP. They'll be getting tidy discounts.