I was VP of Engineering at Altavista in 2000, and I started the project to move to Linux. It wasn't easy because search engineering was populated by Alpha fans who were unswayed by the 10x cost advantage.
As late as 2001, I sat in multiple focus groups where all the enterprise customers said Linux was not yet ready for the datacenter. IBM's penguin campaigns were just beginning at that time.
Google's large scale use of Linux was groundbreaking when they launched in 1998.
Altavista was started by Paul Flaherty. One of his jobs was to find some way to showcase Alphas.
In the late 90s SPARCs did fail. Yes, they were more reliable than commodity x86 boxes, but they failed often enough that it was an issue if you had 100 or so, and search engines hit that level very quickly.
We're talking matter of degree.
The claim was that building a search engine out of 90s sparcs meant that you didn't have to worry about things dying.
That claim is not true - reasonable search engines of that era required enough machines that the failure rate of 90s sparcs, while better than x86 of the time, was enough to require folks to handle frequent failures.
It's reasonable to argue that the cost/benefit tradeoff of sparc's extra reliability vs x85 wasn't worth it for those companies, but that's a different argument.