First of all, I'm going to assume you aren't including microwaves into things. Some of them can hold a truly enormous amount of data, something on the order of thousands of channels. For instance, the highest band is 241-250 GHz, which could hold about 10,000 FM radio quality (200 kHz) stations at the same time.
Comparing 2m to 10m, let's look at the band plans, and see what we can gleam. I'm getting this from ARRL. One big thing to note is that 10M has some FM signals, but is primarily SSB, while 2m has some SSB, but is primarily FM:
10 Meters (28-29.7 MHz)
28.000-28.070 CW
28.070-28.150 RTTY
28.150-28.190 CW
28.200-28.300 Beacons
28.300-29.300 Phone
28.680 SSTV
29.000-29.200 AM
29.300-29.510 Satellite Downlinks
29.520-29.590 Repeater Inputs
29.600 FM Simplex
29.610-29.700 Repeater Outputs
2 Meters (144-148 MHz)
144.00-144.05 EME (CW)
144.05-144.10 General CW and weak signals
144.10-144.20 EME and weak-signal SSB
144.200 National calling frequency
144.200-144.275 General SSB operation
144.275-144.300 Propagation beacons
144.30-144.50 New OSCAR subband
144.50-144.60 Linear translator inputs
144.60-144.90 FM repeater inputs
144.90-145.10 Weak signal and FM simplex (145.01,03,05,07,09 are widely used for packet)
145.10-145.20 Linear translator outputs
145.20-145.50 FM repeater outputs
145.50-145.80 Miscellaneous and experimental modes
145.80-146.00 OSCAR subband
146.01-146.37 Repeater inputs
146.40-146.58 Simplex
146.52 National Simplex Calling Frequency
146.61-146.97 Repeater outputs
147.00-147.39 Repeater outputs
147.42-147.57 Simplex
147.60-147.99 Repeater inputs
Okay, for simplicity I'm going to just block these into total SSB and FM signals, and ignore anything else.
- 10m- Total of 180 kHz FM, 1 MHz SSB.
- 2 100 kHz SSB, 3.5 MHz FM (Or so)
And the channel bandwidths are:
- SSB- 3 Hz (2.8 technically, but...)
- FM- 15 kHz.
Note that SSB takes up a lot less space than FM. Given that, here's the number of channels per band:
- 10m- 334 SSB, 12 FM
- 2m- 33 SSB, 200 FM
Bottom line is, due to the efficiency of SSB over FM, more channels can be used on 2m than 10m at the same time.