The M1 Max has always been able to support multiple displays.
Only the entry level M1 (not Pro or Max) models (13" MacBook Pros) supported only one display.
14" and 16" MacBook Pros with the M1 Max CPU support up to 4 displays, while the M1 Pro CPUs support up to 2 displays.
MacBook Pro (14-inch, 2021) - Technical Specifications
MacBook Pro (16-inch, 2021) - Technical Specifications
Display Support
Simultaneously supports full native resolution on the built-in display at 1 billion colors and:
- Up to two external displays with up to 6K resolution at 60Hz at over a billion colors (M1 Pro) or
- Up to three external displays with up to 6K resolution and one external display with up to 4K resolution at 60Hz at over a billion colors (M1 Max)
Any Thunderbolt Dock that can connect to 2 of Thunderbolt ports on the Mac can offer support for multiple displays.
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