The 16-inch MacBook Pro has faster processors, Wi-Fi 7 support, and twice-as-fast storage that now starts at higher capacities, making it a compelling upgrade option.
macOS Tahoe 26.3.1 update will "upgrade" your M5's CPU to new "super" cores
Older M-series Macs (M1-M4) receive no performance core changes in macOS 26.3.1, while new Studio Displays require the update and feature upgraded A19 chips with enhanced Mac communication capabilities.