One of the limitations of the M1-based Macs is that they are limited to 16GB of unified memory or RAM at the maximum. It is expected that Apple will resolve this limitation with its upcoming refresh of the 14-inch and 16-inch MacBook Pro, but a new rumor indicates that might not entirely be the case.
YouTuber Luke Maini claims that Apple will offer the upcoming 16-inch MacBook Pro with a maximum of 32GB RAM/unified memory, with 16GB of RAM being standard across all configurations. For comparison, Apple offers the Intel-based 16-inch MacBook Pro with up to 64GB RAM. Prior to its design refresh in 2019, Apple offered the 15-inch MacBook Pro with a maximum of 32GB RAM.
Apple may offer the 16-inch MacBook Pro with up to 32GB RAM due to a limitation of the M1X chip powering the machine. Another reason could be the lack of demand for the 64GB RAM option, though power users tend to go with as much RAM as possible while buying a new Mac.
Apple Silicon-based Macs technically feature unified memory instead of RAM. This unified memory is shared between the CPU, GPU, and other system resources to offer better performance and faster data sharing. This is why many power users can use their M1 iMac or Mac mini with just 8GB of memory for heavy usage without any issues. The unified memory architecture may make up for the missing 64GB RAM option on the upcoming 16-inch MacBook Pro.
Another rumor surrounding the 2021 M1X MacBook Pro recently claimed that the machines would feature a UHS-II SD card slot and a backlit Touch ID button. Apple is expected to unveil the redesigned 14-inch and 16-inch MacBook Pro in late Q3 or early Q4 this year.