I2C was originally designed for various chips on one PCB to talk to each other. It has been extended a lot since then but it is still limited.
It is quite sensitive to the capacitance of the wires you use. Longer wires have more capacitance so that defines the length limit.
I have had good luck with SPI over distances of 3-5m but other people have had problems at that length.
Older interfaces like RS232 and RS485 are more suitable for an industrial environment with motors giving off lots of interference. That requires more hardware than just bare Arduinos.