There's lot's of things government could do. Start with codifying some concepts that define when a service is responsible for having too much impact on a user's life, and attach responsibility to that, instead of just 'private company, do anything you want'
It's not an accurate or sufficient or desirable representation of reality to allow these various big companies to actively seek out having you entrust them with parts of various critical paths in your life, and then be able to nuke those with no protection or recourse on your part.
In 1975 when no one had an email address or a cell phone, and neither were required to do anything in life, it was fine to treat them like luxiries that if you lose them, so what?
That was still true but just a bit less so a few years later, and it's just been gradually becoming less so every year, and by now, it is simply not true at all.
It should essentially be illegal for a service provider to completely break some of these services without some sort of graceful shutdown or hand-off process, in the same way and for the same reasons it's illegal to shut off electricity and gas and phone in a lot of cases even after the subscriber has failed to pay. They get shut off eventually of course, but there are exceptions and ways for the subscriber to fight, and they are mandated by the government, not out of the goodness of the power companies hearts. Basically the power company isn't allowed to just let grandma freeze in the winter even if she fails to pay. It's not unfair to the power company. The investors in the power company are free to be in some other business if they don't like those terms.
Today, an email account should not be treated the same way as a spotify account, even if you're not even charging money for the service. If you don't like that, you don't have to offer an email service at all.
The requirement I imagine is some minimal level of continued function enough to complete other account management procedures, which means being able to both receive and send at least some emails. Maybe a limited amount, maybe limited attachment size etc, but enough to at least send the one or few emails from the previously recognized address to other parties as part of the proof of identity to direct them to a new address.
This even in cases where the account was terminated for supposed cause like illegal activity.
This means that one of the other things government can do is recognize that exception for liability. The government can determine not to penalize a service provider or allow others to sue them for having one of these accounts active at that limited level of functionality if the account sends someone a phising email or something.
Or maybe the procedure is the accounts do stop functioning so no email is passed, but, it can still be used by the owner to contact the service provider to invoke some kind of recourse procedure 9f they need it. So the spammer is blocked but mom can still jump through hoops and eventually regain access, including old mails and maybe even including unread received mails while it was down.
There are all kinds of things a government can do, and fully fairly and defensibly and officially, just by codifying some principles.
What do I expect from the government? Something. They can absolutely do something. It's work to work out exactly what and how and develop some consistent rational legal theory to base it on, but that it literally their job is to to exactly that.