The recent tax law changes completely disallow the expensing of on site meals provided to employees. It has already started phasing out and might be fully phased out by 2021 if I remember correctly. So the IRS doesn't have to fight that anymore.
So they can still provide it to employees, but if they want the tax deduction, they will have to itemize it on employee compensation, which will cause them to pay taxes on it as income.
Seems about par for the course. I'm sure a lot of policy would have to be enacted to allow something like that, and my company (also a large tech company) announced something similar not too long ago.
https://www.businessinsider.com/irs-and-free-food-at-tech-co...
Expensing WFH lunches would give IRS more ammo to tie the food to taxable individual employee benefits.