It is also fire and forget with fall over to http if web sockets aren't available. I believe if web sockets don't work it can fall over to http long polling instead, but don't quote me on that.
All the downsides of web sockets mentioned in the article are handled for you. Plus you can re-use your existing auth solution. Easily plug logging stuff in, etc. etc. Literally all the problems mentioned by the author are dealt with.
Given the author mentions C# is part of their stack I don't know why they didn't mention signalr or use that instead of rolling their own solution.