There are many folks who reflexively append .com to everything. Even if it redirects to .gov someday, depriving fraudsters of the .com is absolutely worthwhile.
My email address is firstname@lastname.me. The amount of times I've dealt with customer service... "We have your email address as firstname@lastname.me.com" or similar is notable.
I have firstname@lastname.io (younger me got swept up when .io was a big thing). Customer service gets confused, but also occasionally websites will tell me it's not a valid domain and I have to fall back to Gmail.