The platform.txt is not read by PlatformIO, no use in copying it.
What exactly do you want to achieve? The 2.0.0 core with an S2 board? There are still multiple issues for these kind of boards and integration is being worked on by staff (Support for the latest Arduino v2.0 · Issue #619 · platformio/platform-espressif32 · GitHub) and is not yet done. Best to not do custom hacks.
For ESP32 boards (not C3 or S2), see Use different version of Arduino framework on espressif platform - #6 by maxgerhardt if you really want to try it.