Hello Klaus, my dear old friend, nice to have you finally here

,
But: the performance of the recording lenses is getting better and better.
Yes, indeed! In the last 30 years huge improvements have been made. Good for us photographers.
Sometime in the future, films with a better resolution (maybe 200 Lp/mm) might be necessary.
No, not necessarily. Because as film photographers we can fully benefit from the amazing modern lenses! The improvements they offer are transferred onto our current films, and clearly visible.
As you have mentioned resolution:
The "rule of thumb" which works quite well in practical terms is for our imaging chain:
1/system resolution = 1/lens resolution + 1/film resolution.
So you see immediately: With the same film you get higher resolution if you are using a higher resolving lens. And vice versa.
I have done more than 10,000 of such tests over the years in my photography test lab. And I can absolutely confirm that this is really working in that way! Better lens = better performance with the same film. Excellent for us film photographers.
Digital is different, as in most cases the resolution is limited by the sensor, by the Nyquist frequency. In film photography that problem does not exist fortunately.
Modern lenses and the highest resolving films like ADOX CMS 20 II, ADOX HR-50, TMX, Delta 100, PanF+, Acros II, Velvia 50 and 100, Provia 100F etc. are an excellent combination, offering amazing picture quality.
As an Agfa APX 25 fan (still have some

) I would like to see such a film again, too. But the films mentioned above are so good that I can live a happy photographer life with the existing films

.
Best regards,
Henning