The patents expired in 2010, and it should be enabled by default starting from Freetype 2.4. Microsofts patents on ClearType color filtering expired in 2019, but I don't know if that has led to any further improvements in Freetype.

https://freetype.org/patents.html

Make sure you don't have this in your fontconfig:

  <match target="font">
    <edit name="autohint" mode="assign">
      <bool>true</bool>
    </edit>
  </match>

As the autohinter is garbage.