Postal application for entry visa at this point works only for those not in a hurry, or those yet to make travel plans.
There are lots of people who booked tickets and made plans months ago for November or December, planning to apply for e-visa a later. Now they do not have the luxury of wasting a week to 10 days for BLS to look into a mailed-in OCI or entry-visa application, and then have it returned for some flimsy reason, or wait for the consulate to take 45 days to process it. That is why we've been seeing folks wait in line overnight at the BLS office hoping to get a walk-in token.
When people come here and tell why don't you apply by postal or use appointment, or (now) try to get an entry visa, they are missing the point. Great advice in normal times, these are not normal times.