Yes, 6.20 to 6.72 is a nice jump because the 6,20 is same like 6,72
you can try the 6.20 but no nice Exploit Host exist only is this
https://github.com/ChendoChap/ps4-ipv6-uaf/tree/6.20
i was too on 6,20 FW and was thinking is maybe stabler as 6,72 because people talking for 2 years about random crashes on Exploit .. but this was for me on Firmware 6,20 too with ps4-hen-vtx i tried to Port the Payloads to Firmware 6,20
https://github.com/ps4gentoo/ps4-hen-vtx/tree/620 but its to mutch work for me so i updated too because
@Leeful was bringing out hes nice Exploit Host for Firmware 6,72.
if you just want to play games i recommend you just upgrade to 6.72 so you don't get a headache. have fun with your PS4 Pro.
the only thing on 6,20 <--> 6,72 the webkit has an older version and GoldHen is only released for 5.05, 6.72 and 9.00 Firmware
https://github.com/GoldHEN/GoldHEN
some people on fw 9.00 say that the exploit is more stable (no random crashes), but I don't like this USB variant ... maybe they port this exploit to other versions ... 6,72 ... 6.20 .... so we can test this variant also times on FW 6.72. ...but ya...easier said than done.
https://github.com/ChendoChap/pOOBs4
The bug predates firmware 1.00, so 1.00-9.00 should be exploitable using the same strategy (you will need a different userland exploit & gadgets).
if you want headcaches stay at 6.20 :-)
https://www.psdevwiki.com/ps4/Working_Exploits
this exploit would be interesting for 6.20 but Specter stopped working on this, now he works on PS5.
https://github.com/Cryptogenic/PS4-6.20-WebKit-Code-Execution-Exploit