It starts with much worse quality (not Linux' fault), like worse displays, borderline unusable fingerprint scanners, etc.
But beyond that, I regularly get kernel panics recovering from sleep with a Thunderbolt display connected (last time I checked the exact DDC-related bug has been open for a while). With some displays the USB-C get misconfigured (another known bug), resulting in worse frame rates. Sometimes hardware doesn't come up after a resume.
Battery life is generally much worse. Even if you hyperoptimize it with powertop, etc. battery life is still much worse. Not only that, but it puts Bluetooth and USB in autosuspend, which often breaks waking by using an external mouse or keyboard. Even if your laptop still supports S3 sleep, the system often runs out of battery while suspended in 12-24 hours (yes, it's fully suspended and does not wake).
I could go on for a while, it's death by a thousand paper cuts.
We have a bunch of MacBooks in the family. They are insanely fast, batteries last forever, and I cannot remember the last time I had a panic. Displays always work between Apple Studio Display, Dell Thunderbolt, and a bunch of USB-C LG displays.
But yeah, I'm still keeping a Linux laptop around, just in case Apple restricts macOS more, extends their surveillance capitalism, and other contingencies.