Plenty of outright wrong stuff in that response. How was Tesla 'absolutely critical'? Dolivo-Dobrovolsky demonstrated a working polyphase system several years before Tesla worked on it. There were quite a number of working commercial AC plants/systems in Europe by the time Tesla/Westinghouse opened theirs Niagara in 1895. It was not even the first commercial AC system in the US, that goes to Almirian Decker's Redlands plant in California. The first demonstration system in the US was created by William Stanley, Jr in 1886.

So how were Tesla's contributions "absolutely essential"? Because Westinghouse gave him a sweet royalty deal because he had a patent? He patented a lot of stuff, some of them well after other people had invented and published them. (e.g. Ferraris three-phase motor design, which he provably published before Tesla patented it. The only basis for claiming that Tesla invented it first is basically because Tesla said so)

Tesla was a huge self-promoter (and quite similar to Edison in that regard), a guy who took full credit for things he knew damn well that other people had made important contributions to (if he wasn't outright ripping them off), a nut (although the Oatmeal agrees there), and a patent troll.

And somehow he's an "Unsung hero"? The only unsung hero with a friggin' SI unit named after him, his face on the currency of his home country, not to mention a full-blown circlejerk among people who have no clue who Steinmetz or the other guys I just mentioned were, or what they did.

Did Tesla make important contributions that were undoubtedly his own? Yes. But would DC have won the "War of the Currents" without him? Absolutely not. AC would always have won. It may have been a minority of electrical engineers in the US (not Europe) at that time who were pursuing AC, but it was far from Tesla alone. Forbes was entirely correct in pointing out that the "War of the Currents" never really existed in Europe, or even outside of the northeast US. The "war", Edison vs Tesla, GE vs Westinghouse, is a dumbed-down media narrative.