10 years ago an Italian colleague resident in Zurich at the time was getting Swiss fines in Italy (he commuted weekly for a year). So Italy is covered.

I have been fined in 2005 in Germany for a Swiss infraction in Zürich so Germany is covered.

Germany and Austria recognize each others points for some years now, like Ireland and UK are about to including bans starting with Northern Ireland.

One of the open questions is if Switzerland will start with points and agree a points exchange program.

It's all part of the EU driving license program to gradually exchange more and more info beyond just recognizing each others licenses. Even within the EU this is being done bilaterally for legal reasons.
One of the issues is the multiple still valid versions of licenses per country (there's a document on it on the EU website).
Another is the lack of consistency of points offences and fines for the same offences (see the table the TCS/DAS produces each summer).
Finally the EU realises it needs to recognize bans EU wide as it's still legal after a ban to pass a driving test in another EU state and drive back home without going through special arrangements applicable in your home state (like in Germany).
This is also possible as the rules on residency to qualify for license testing/issuance are light. In addition exchanging can clean your record from another state's point of view.

I agree with the pragmatic motivation mentioned earlier for the Swiss probably best summarised as: "Gibts geld?....OK".