I was shooting TMAX 100 in 67 format, mostly. Scanning was done on a Minolta Dimage Scan multi Pro at 3200PPI. I was not really looking into MTF50, but I have measured MTF 50 on Velvia shots and came in around 2300 LW/PH for 67 against 2900 LW/PHon my Sony Alpha 900. My equipment may matter, I have a Pentax 67 with the lenses 40/4, 90/2.8, 165/2.8 and 300/4, neither lens is known to be ultimately sharp.
I did scan some TMAX 100 from 67 and was not really impressed. All testing I recently made was on color, as I never shoot BW now days.But my message is that scanning B&W film is not really easy
Regarding lens resolutions, I recently checked out sample images from Imaging resource on Alpha 700 (12MP), Alpha 55 (16MP) and Alpha 77 (24MP) using Imatest and found that LW/PH followed sqrt(MP) very closely, so it seem that lenses outresolve sensors. I checked the A77 for three reasons, BTW. I have it on order, it is using the smallest pitch on any DSLR and I wanted to compare it to the NEX-7.
I was specifically using the extreme case of fine-grained monochrome film: color film (horrible stuff to scan, and lower resolution) was probably matched for resolution several sensor generations ago. At the Norm Koren page cited above, the highest MTF50 for any color film is 63 cycle/mm for Fujifilm Superia 100, and that brings my pixel count comparison down to "over 14MP", and less for Velvia. Does that fit more with your observations?
Back to the extreme case of fine-grained monochrome films: by all measures I see, T-MAX 100 has even better resolution that the famous but now discontinued Technical Pan:
Technical Pan MTF curves on page 9 of http://www.kodak.com/global/en/professional/support/techPubs/p255/p255.pdf
T-MAX 100 MFT curves on page 14 of http://www.kodak.com/global/en/professional/support/techPubs/f4016/f4016.pdf
Note that I stayed away from the "film is great" fanboyism by using MTF 50, not extinction resolution relevant only to very high contrast targets.
I meant the mainly as one way to get a reality check on the alleged inadequacy of 35mm format lens resolution. To DIY, dust of your old (Minolta?) 35mm film body, load some T-MAX 100, take some carefully focused photographs, scan carefully (or be old fashioned and print large!), and look.