I think there is a difference in the fact that we could keep a 20% APR, not that we should.

20% may be scary for outsiders as that number may sound too good to be true.

HIVE is down significantly from last year, so with HBD yield so high HIVE is not attractive at all.

I set my witness to signal for a 16% APR, but even the proposed 12% is still attractive and beat other DeFi protocols.

With 2 digits of APR we will still keep the supply of HBD increasing steadily.

Yes, we could leave it at 20%, but the ones who were profiting from 20% were people that already used HIVE and already had HBD savings. We did not manage to attractive new users just because of the high APR, so sounds like a reasonable time to me to make HIVE attractive again to get blogging and curating attractive again and keep users engaged in the social aspect of HIVE instead of the DeFi yielding aspect of HBD, which will still exist, still be strong and still be competitive and among the best options out there even at 10% or 12%

What if we apply the same rule of "if it is not broken don't fix it" to lower APR? We lower it, test it, if it is not broken we leave it low, if it is bad in any regard we increase it again.

If we consider that 12% is still a high and very attractive APR the same arguments for 20% are still valid for 12%, the only difference is greed for bigger and bigger numbers
But if we consider that 12% is low, then we are out of touch with reality because 12% yield on dollar is not low