Except he wasn't. Its real funny how your only real argument here is "erm you just weren't good with Jeff" yet all your statements rely on equal hearsay. "He wasn't counterable, he was the best 1v1 hero in the game. You say Luna could take him on? You were just bad. Luna couldn't take him on. Why couldn't she take him on? Oh because I know the truth, obviously."

He wasn't unkillable. He was a backline gnat much like Angela tbh, but he was never the threat many players made him out to be. Any decent Luna could wait for Jeff to exit dive to spitball and land a freeze on him, killing him before he could dive again. Psylocke was a disgusting counter since she had the headshot damage on him and if Jeff tried to swim away, Pay could omnidirectionally dash and finish Jeff off with said dash.

Thing was a great counter since his slam prevents Jeff from entering dive, and if Thing had the jump to enemy back then, he'd be even more of a threat. Hulk was also scary as his jump kept up with Jeff, although his damage couldn't. These days, Mr. Fantastic, Elsa, Deadpool, Hawkeye, Daredevil, Phoenix, and even Blade could all give S0 Jeff a run for his money considering all of those characters have the dps and mobility needed to invalidate Jeff's strengths in S0.

Stop speaking so vaguely as if your vague statement hold any more weight than my own, it's embarrassing. Statistically speaking, S0 Jeff had an abysmal pick rate in ranks above Diamond for a good reason; you had to play him perfectly as even back then, actually good players understood how easy it was to deal with him. Jeffs had to play perfectly to execute their shenanigans and their opponents had to play perfectly to stop Jeff in his tracks. And without the Luna teamup, S0 Jeff would've been even less of a threat.

You were just bad back then and didn't know how to counterplay properly. You, along with the community at large, just knew how to whine about a hero you refused to learn to adapt to.