One does not even need to squint. The first page of RFC 882 explains outright that the DNS came about in the first place because the mechanisms for updating a HOSTS.TXT file and publishing it to loads of places did not scale.

That's still just as true for the intranets of the 2020s with thousands of machines all downloading a HOSTS file several times a day (or even hour/minute) as it was for the Internet of July 1983 with around 500 hosts that was merely downloaded by everyone a couple of times per week. The fact that a file can be copied faster now is counterbalanced by the fact that tying this to real-time failover means that it needs to be updated and distributed several orders of magnitude more quickly than it was in 1983 too. And that's ignoring the linear nature of a HOSTS file lookup contrasted with even the stupidest DNS implementation.

Those who think that HOSTS is a fallback for any sort of dynamic operation (into and out of service) of even hundreds of machines have not learned the history of why the DNS even exists.