That´s actually admitting a mistake, or admitting having commited a crime. I assume that was the easiest and fastest way to end this tragedy of a law suit, but I think it leaves a sour taste to it, not against Telegram but to regulatory folks
They did run an unregistered security sale, and that's illegal. If they tried to fight it, they'd very likely ended up with a much higher fine and some lawyer fees on top of it. You may consider it not immoral to run an ICO, but it is against the current laws.
And from my point of view, you don't need $1.2 billion to make a token, a million or two should be more than enough, and Telegram, being a big company, could have easily afforded that.