No, that TOS was amended several months ago, to among other things, get rid of that clause about termination for any reason. "We used to be able to terminate your account at any time and for any reason. Now, we can only do so if you: fail to comply with the Terms and Conditions; if we are required to by law; or if your account is inactive for an extended period of time." [0] [1]
[0] https://blog.fastmail.com/2017/09/11/tos-update/
[1] https://www.fastmail.com/about/tos.html