It's not about age. I'm rather oldschool, and I like programming ligatures very much. When => intended to imitate thick arrow, seeing thick arrow instead is reasonable, I think
If languages opt to make “≠” equivalent to “!=“, match all styles of open/close quotes, and enable me to attribute a value to a variable using an arrow, that’s great.
In the meantime, I’m not sure they are a net positive in all cases and fear they may drive unfortunate syntax choices for people who design languages.
It's possible in Emacs: to enable relevant ligatures for an active mode.