For now...the market share of vehicles with alternative propulsion in CH (hybrids, pulg-in hybrids, natural gas, and pure battery EV) is 25% this year. Pure battery electric vehicles market share is 6.9% from so far from Jan to Oct 2020, up from 4.2% on 2019 and 1.7% on 2018.

https://infogram.com/marktanteile-al...h7k23gnzg0g4xr

So, we could assume the collection of this tax has at least gone down 7% at federal level. Don't know if specific cantons have seen greater tax collection decrease due to higher EV market share. Also, EVs don't pay the 73 rappen fuel tax for road infrastructure. Since the fraction of EVs keeps increasing, at some point EVs will have to pay tax too on one way or another.

I bet 2 beers that when EVs reach 20% of new passenger car sales, some tax changes will come. 2022 or 2023? Not tomorrow but it starts to impact the people buying an EV today.