From NixOS Wiki

Clickpad issues

If your touchpad physical click (or clickpad) like for Lenovo Thinkpad or MacBook touchpad is disabled after a kernel update, this might be due to a kernel bug on the 6.1+ Linux.

To restore the previous behavior, add to your Nixos hardware configuration:

  # Avoid touchpad click to tap (clickpad) bug. For more detail see:
  boot.kernelParams = [ "psmouse.synaptics_intertouch=0" ];