If you reframe the issue from "Nepal wants to punish the users" to "Nepal wants to punish the companies", implementing an easy DNS block makes a lot more sense. As long as most users are unable to access the platforms, the companies will get hurt by it, I think the idea is at least.
See, companies that deal with a lot of traffic on static data have geographically distributed caches.
Let's say Steam has a major game release, and gets slammed with the DL traffic of 5 million gamers all around the world trying to get their hands at that new game all at once. However, Steam has an instruction manual that allows any ISP to set up their own cache servers. So an ISP that has a cache set up can convert a lot of that global traffic to local traffic, saving them money, and offering users a better experience.
(One small ISP I knew had it set up so that all traffic to their local Steam cache was fully exempt from client rate limiting, reportedly because the ISP's admins were avid gamers.)
Other services like major CDNs, YouTube or Netflix may have deals with ISPs to locate their caching hardware on ISP premises, or may buy their own caching servers in specific datacenters. Same idea applies - it's cheaper for both ISPs and web services when the users hit local caches than when they "cache miss" and generate global traffic.
VPN use is a "forced cache miss", so it's a loss-loss for both ISPs and web services.
Also mentioned here, larger corps have local caches which unloads transit significantly. Google does this for YouTube everywhere.
These plans all include unlimited data and an Xfinity gateway.
You aren't required to use their gateway, although they will still ship one to you unless you ask them not to. There is no discount for not using it. Unlimited is tied to the account, not the modem or gateway so you still get unlimited if you use your own modem. Same if you use their gateway but put it in bridge mode and supply your own router.
For new customers each of the new plans can be gotten at an introductory discount. The discount price is guaranteed for 1 year or 5 years (your choice, with 1 year generally giving a steeper discount). These are all month to month plans so you aren't locked into a contract.
Existing customers can switch to the new plans. There is no discount but they do get the 1 year or 5 year price guarantee.