She asked for an extension to complete her treatment, or at the least a short period to consult with her medical providers about whether and how she might be able to return to work before the treatment was completed. Instead, MongoDB terminated her health insurance and then fired her in violation of the Americans with Disabilities Act and the New York State and City Human Rights Laws. Shortly afterward, Annie took her own life.

Maybe, as a VERY FIRST STEP, don't act in violation of human rights laws. It seems, based on what was linked in this post, that she was trying to figure out how to best move forward (not just for herself but also in reapects to her returning to work) when they cut her off.

1. Illegal to fire someone on leave, no exceptions.

2. Healthcare related leaves (employee paychecks for the time) are partially (eg 80% or everything over 3 days or whatever the country codifies) covered by the government.

3. Shaming the employer who now has a hard time to find workforce.

I thought this was the norm outside of USA.
And something that employers still exploit via 'consensual termination', which usually involves some kind of extra compensation, but it's not regulated per se, just wherever a person in power is able to get the other one to agree to. Still better than no protections or warnings I guess.

Oh, reev already pointed out that that practice is against the law as it is now. But healthcare shouldn't be tied to your employer/employment status.