Because OLS uses LSPHP, and not PHP-FPM, so these settings are ignored. The php.ini settings are followed by OLS.
All you can do is set NPROC (package settings or overrides) and/or LSAPI_CHILDREN (overrides only). We set LSAPI_CHILDREN to NPROC + 3 or so, and set NPROC calculated based on the other package resources like RAM and SWAP.
For standard hosting packages, like RAM allowed to 0.5-1GB or so, NPROC of > 15 can easily consume all RAM when a bot hits your site just mildly, then lead to swapping and get stuck indefinitely with http-503s (as the Enhance setup of OLS doesn't allow automatic restarting if 503s are detected).
You'll have to pin the RAM, SWAP and NPROC in the package settings based on the actual requirements, or your sites and servers will continue to get wrecked all the time. You want these sites to bounce back a few 503s to bulk requests because of exhaustion of NPROC and NOT because of RAM/SWAP being exchausted.
