I have been out of the field for some time, so I am not sure how much BLAST is used these days.
Therer was a time when BLAST-ing a DNA and protein sequence you have is like doing a Google search on it: it simply tells you where the sequence might come from. This is useful especially when your research is to figure out what that specific sequence is doing. It won't give you the answer immediately (otherwise why bother doing the research at all), but it certainly gives context: sequence similarity often hints at similar / related functions.
As an analogy: imagine if StackOverflow is suddenly down and you don't know *if* it's going to be up again.
My sibling is a molecular biologist working in the industry and they do use BLAST data. She's been telling her company for months they need to secure access with an alternative source or offline backup, hopefully their software team started it in time.
Everyone can set-up their own blast database. Usually if you are specialized on a certain species you have your own DB cached in memory somewhere locally for efficiency. Also there are alternatives. NCBI blast is just one of many. Also all the sequences are globally kept and in sync in different regions of the world, so if one Datacenter goes down you still have the option to use the exact same data from Europe or Japan and so on.
Fair, and to be totally clear, even when I was in the field (an age ago), sequence stuff was never really my thing. However, sequence comparison is a fairly fundamental tool.
Of course, yes you can run these things locally, other providers (such as EBI Europe and Japan) have them, etc. It's still a bad sign on the pile of other bad signs, IMO.
Not a professional, but still use it like that. They also have a new smartblast thing, which works much faster (really, really like Google!) but only on highly similar proteins.
Therer was a time when BLAST-ing a DNA and protein sequence you have is like doing a Google search on it: it simply tells you where the sequence might come from. This is useful especially when your research is to figure out what that specific sequence is doing. It won't give you the answer immediately (otherwise why bother doing the research at all), but it certainly gives context: sequence similarity often hints at similar / related functions.
As an analogy: imagine if StackOverflow is suddenly down and you don't know *if* it's going to be up again.