The freedom problem is this: you will not be able to roll your own keys.
This is probably the biggest nail in the coffin for a ton of computers out there. In theory you could simulate via software the workings of a TPM. If you built a kernel module the browser would have no real way of knowing if it sent requests to a piece of hardware or a piece of software. But the fact that you would have to use Microsoft's or Apple's keys makes this completely impossible.
The hardware problem is this: you will not be able to use older or niche/independent hardware.
As we established that software simulation is impossible, this makes a ton of older devices utter e-waste for the near future. Most Chromebooks themselves don't have a TPM, so even though they are guaranteed updates for 10 years how are they going to browse the web? (maybe in that case Google could actually deploy a software TPM with their keys since it's closed source). I have a few old business laptops at home that have a 1.X version of the TPM. In theory it performs just as well as TPM 2.X, but they will not be supported because, again, I will not be able to use my own keys.
Lastly there is the social problem: is DRM the future of the web?
Maybe this trusted computing stuff really is what the web is bound to become, either using your certified TPM keys or maybe your Electronic National ID card or maybe both in order to attest the genuineness of the device that is making the requests. Maybe the Wild West era of the web was a silly dream fueled by novelty and inexperience and in the future we will look back and clearly see we needed more guarantees regarding web browsing, just like we need a central authority to guarantee and regulate SSL certificates or domain names.
if they control your computer, they can prevent you from incurring in 'illegal' activities such as piracy
but it all boils down to the logic of the market, the raw fact that capitalism works even with marginal costs. but when copying (and distribution) costs go lower (less than 'marginal' down to zero cost) it all starts to break down
if people aren't selling digital assets to each other (which doesn't make sense with the technology we have right now), they cannot be taxed and so on.
solution: fix the technology. make it so that only those with specially authorized keys (trust worthy actors) can copy digital information at will. everybody else will have to pay them for this privilege.
oh and nevermind the fact that computers work by copying bits all over the place