Maybe so. In which case, I'd say I disagree. Great crawling ability is definitely a necessary, but not sufficient, condition for building a competitive search engine. And while the technical aspects of building a large scale search engine have been at least partly trivialized by OSS crawling software, elastic computing resources in the cloud, etc., what is at issue is the possibility of site owners blocking anybody who isn't (Google|Bing|Baidu|etc).
In this context, that's my concern: being blocked from crawling, if you're not already on the "allowed" list. Hence my reference to the question quoted above, from TFA.
In one aspect, it was literally their beginning, from which they were able to build a business and expand.
In another, much more on point aspect, it underlies the majority of their services, either directly of a few steps removed.
Like the foundation of a house, it may not always be the most visible aspect, and it may be taken for granted, but its contribution to the integrity of the whole can't be underestimated.
Yes, but I think the comment you responded to were saying that it is an insignificant part these days.