Instead it uses Tor network [...]
Are you sure? Do they use that alongside the weird blockchain backend they had going, or switch over at some point? I remember looking into Session awhile ago but I wrote it off because of the blockchain/cryptocurrency shenanigans involved in the architecture.
As I recall part of the idea was that the cryptocurrency would serve as a sort of incentive for people to run nodes for the Session network to operate.
In principle I'm inclined to agree, however isn't this glossing over the degree to which markets are consolidated?
You try to opt out of products/services and choose more ethical alternatives, but it turns out the most readily available alternatives are in some way connected to the same unethical parent company. Ultimately the individualistic approach to addressing these matters is untenable and requires collective action in some form (ideally it would be leveraging a government that reflects the interests of the people).