This sort of benefit in software can be realized with much shorter terms. A 5 or 10 year term would accomplish pretty much all the same benefits. 25 years is just way too long for software.
The benefit comes from no one ever using the earlier inferior versions.
Correct. 5 years is long enough to kill off inferior standards and let superior ones blossom.
if it's inferior, why does it matter if it's 5 years or 25 years ?
Why do you think it always only takes 5 years to develop some superior technology? 5 years seems like a short enough time frame that a company would rather just wait out the patent than invest heavily in R&D in the off chance they come up with a viable alternative (that now of course THEY can only protect for 5 years)