You can easily get Arduino-ESP32 3.x into PlatformIO. Just set the platform to a fork that supports it. There’s posts about that all over this forum, e.g. How do I determine release version of arduino-esp32 used in latest framework-arduinoespressif32? - #2 by maxgerhardt
If you set
platform = https://github.com/pioarduino/platform-espressif32.git#51.03.04
you’ll get Arduino-ESP32 3.0.4.