Drawing text / graphics to the OLED on a Pi or micro:bit is much slower than with the Pico for two reasons:

• it appears that smbus2 is streaming each byte out as a single i2c transaction, rather than grouping into multi-byte transactions
• the framebuffer is handmade for Pi and micro:bit, with nested looping (very slow in python)

The outcome is that the Pico can support a high fps, while RPi and micro:bit experience single-digit fps.
A related CE forum topic

Proposed solutions:

• port PiicoDev_Unified.py to use pigpio instead of smbus2. This is a major port that would not be backwards compatible
• investigate using @viper functions for resource-intensive methods like text().