As of this writing, there have been four generations of Apple CPUs, the M1, the M2, the M3, and the M4.  Each generation has offered three variations, a ‘base’ model (without a suffix) and ‘Pro’ and ‘Max’ models.

Mac laptops based on Apple CPUs have varying native external display capabilities via Thunderbolt/USB-C connections.

Each generation offers different capabilities depending upon which generation and variation of Apple processor is in use.

As of this writing, the M4 generation is the most capable CPU in regard to native external display capabilities as compared to all previous generations and variations.

Apple Mac laptops with a base M4 processor or M4 Pro processor can support up to two external displays regardless of the state of the laptop lid.

Apple Mac laptops with a M4 Max processor can support up to a total of four external displays regardless of the state of the laptop lid.

Apple Mac laptops with base M3 processors can support one external display when the laptop lid is open and the laptop’s internal display is enabled. They can support up to two external displays when the laptop lid is closed and the external display is disabled.

Apple Mac laptops with M3 Pro or M3 Max processors can support up to four external displays in total, regardless of the state of the laptop lid.

Apple Mac laptops with base M1 and M2 processors support one external display only.

Apple Mac laptops with M1 Pro and M2 Pro processors support up to two external displays.

Apple Mac laptops with M1 Max and M2 Max processors can support up to four external displays in total.