Google will recommend all sites combine these files in fewer, larger files.
However, most sites now use HTTP/2, which prefers smaller files, even in greater numbers.
Your actual site speed may benefit from ignoring this recommendation. However, your scores will benefit from following it.
This is ultimately due to that fact that Lighthouse (the tool that powers PSI) is not looking at your site through the HTTP/2 protocol – even though your site supports it.