Well, de-escalation is rather random. Like, if you played 30 matches(somehow) in the course of a week following a 5 game chat restriction, I'm fairly certain one report after those 30 matches would trigger a 10 game restriction based on my experience. It's extremely slow to heal. I believe banning or suspending over words is ridiculous. That's punishing a conceptual offense, with feasible action. And eye for two eyes. Chat restrictions are good enough.
I've also brought forth an alternative before that had found favor with some of the support staff. But the heavy liberal tilt in this forum quickly shut it down. That beneath the "Allow all chat" box, you include an additional "Allow Toxic Chat" box. Which works in conjunction to toxicity reports and chat restrictions. If you do not reform after a 25 game chat restriction, you are added to a type of naughty list. That when you check that box, it automatically mutes players who have shown no improvements in their chat. So they lose the ability to chat forever. Since if they're winning their games, they're not actively trolling intentionally, There is a spectrum for mental illness as well. They could be at their own mercy. And the eye for an eye argument I made in the OP. Pings would be your last bastion of communication, which when spammed go on cool down more quickly when on the naughty list.
This improves the system, preserves the community, and gives the players more freedom to decide what they believe is toxic. Rather than putting it all on Riot. If players don't heed the chat restrictions, rather than losing their account, they lost their chat. That makes more sense to me. And other players can decide whether or not they care about trash talk or 'harassment', I believe the opinion is popular enough to include the "toxic chat" box beneath "all chat".
"But communication is so crucial!", I don't believe so. A popular counter argument to being toxic is "Can't you just not say anything?". I find pings sufficient. As a Thresh main, I thrive on communication, and they work find, they're fast enough to get my point across. For example; when I ping a low minion, my adc knows to poke it down FAST so I can Q just before it dies to land a surprising hook. I know about communication more than most, and pings are sufficient.