It's an emotional topic but I think it's a combination of equity, office culture, technology and position description.

I was in the position where my work could be done remotely but the office culture didn't allow for it or the office wants to be overly strict about it because they claim equity among employees. So, yes you're right in that position the right to work from home needed to be dictated in the contract.

Now, moving into tech, it feels more like a right to work from home because it's the industry culture. After going to a few tech interviews, it's assumed you will be working from home and it's not written in the contract. (At least what I've seen)

So, the right to work from home is relative depending on your industry. I'm like many others and avoid companies with stringent management which can be seen in the contract.