The rp2040 includes optimized floating point functions in ROM, using linker magic to replace the standard gcc floating point functions when building applications from the pico SDK or Philhower core.

But the Arduino mbed core for rp2040 does not do the linker magic, causing applications that use floating point to be much slower (and larger) than on other rp2040 platforms.

the linker magic is included here: https://github.com/earlephilhower/arduino-pico/blob/master/lib/platform_wrap.txt

Arduino's (much smaller) link options: https://github.com/arduino/ArduinoCore-mbed/blob/master/variants/RASPBERRY_PI_PICO/ldflags.txt