The main issues I can see:

• lack of secure instant communication, like Signal
• missing secure wi-fi protocols
• no TLS >= 1.0 support
• expired root certificates
• backdoors, established digital forensic tools
• credentials stored in RAM

If somehow you can install an SSH v2 client, with 2FA login - will be somehow useful.

My fast research, a PSP with custom firmware, and PSPSSH SSH client (not sure if it supports current ciphers).