Intel version of MacBook Pro can be connected to one 5K display or two 4K displays. The 2018 Intel Mac mini can connect up to three 4K displays or one 5K display and one 4K display. According to Apple’s official guidance documents, M1 MacBook Air / Pro can be connected to an external display up to 6K 60Hz, while M1 Mac mini has a maximum 6K 60Hz screen and HDMI 2.0 up to 4K 60Hz screen.
That is not true as Russian Up master Tulupov found that the M1 Mac mini can connect up to 6 external displays, while the M1 MacBook Air / Pro has 5. Of course, because the interface is not enough, you need to use DisplayPort adapter and DisplayLink software to deploy, but for multi-screen users, it is still a very important discovery.
It should be noted that due to bandwidth limitations, all 6 displays cannot be 4K.
Clearly, the Apple M1 is a lot powerful than we had actually imagined. It takes a lot to power 3-4 high resolution displays, let alone six.