So what ?

They'll just be bought again and the masternode count will re-stabilise at some arbitrary point, except this time not haemorrhaging all the investor capital out of the chain that it did before.

The protocol doesn't control the value of the reward, the market does.

It has already "reduced that payment" and coins have been getting "sold off" for the last 4 years.  You're clinging to a state of Stockholm-syndrome driven paralysis that inhibits action being taken to break this corrosive cycle.