Tails is one of those tools I always keep on me physically. Added it to my key ring 6 years ago , and I get use out of it at least twice a month. Also started using it as a recovery ISO. But my main use case is when I have to use a computer but don’t have mine around . Just pop the USB in and voila all the access I need and my data stored in the persistent partition.
I also spent most of my internship long ago researching secure operating systems for the analysts of the company I worked for and Tails was the best fit with Qubes being second due to how power hungry it is. Another was subgraph but at the time it wasn’t properly developed. Overall if you need a OS that guarantees that all your traffic is anonymised via Tor and that it is ephemeral Tails is superb.