For some OFs (old farts), HAM is written as all uppercase because of the (apocryphal) story of the a station being operated under the "HAM" call sign by Albert Hyman, Bob Almy, and Peggie Murray that came to stand for all of "ham radio" because they made an impassioned plea against a bill in Congress that would have revoked the frequency allocations for all of amateur radio and given them over to the military.

Further, since call signs are always written in uppercase (WRR-FM, KIRO-AM, KBTC-TV), some hams are apt to write the name of the hobby as HAM out of habit/solidarity.

So while you're technically right that "ham" is more of "ham-fisted" or "what a ham" variety, you're not following the internal culture.