PHP runs literally half the web. Half the web will not apply this patch in any reasonable amount of time (a huge portion will never). This is going to be absolutely catastrophic.
What should be done? Can beneficent governments race to hack and patch servers?
So if I wanted to build a botnet, then it would be very easy ;).
Infiltrate vulnerable PHP sites. Install backdoor(s). Secure root access. Patch PHP to lock out script kiddies. Let it sit dormant until you need to launch attack
The union of hosters which will not update to this patch, and users who have not updated to the past 283762 CVE is literally the same circle. I think that maybe a couple new not infected machines will get infected with a cryptominer - the rest will just get one new miner fighting for resources