Classic PR bull poo Rich ! The issues of conversion to hydrogen like the use of EV power are more about the overall system from generation to storage than the basic re-engineering of pistons as made by Mahle. Plus in some minor areas you have to ask whether the effort to find solutions really is worth it.
For example, the two huge transport based "polluters" are cars and shipping. EVs will reduce the car contribution significantly. Shipping being international probably comes under the heading of politically too difficult. You have to ask "why bother" when it comes to the small polluters like earth moving equipment. Reality is that the purity of approach to the issue is likely to cause more problems than it cures.
Have a look at https://www.transport.gov.scot/publication/scottish-transport-statistics-2021/chapter-13-environment/#:~:text=Heavy%20Goods%20Vehicles%20and%20Light,4.6%25%20of%20transport%27s%20total%20emissions.
Some interesting data in there
