Remote and WFH for six years.
Switching off at the end of the day has always been one of the hardest parts, especially since I am in the UK but have worked for companies based in the US. So my day is ending just as my US coworkers are starting to come online and want to communicate. If I don't completely block Slack, etc. I'll get pulled into conversations and end up working late into the evening.
The best I've managed so far, without setting up separate hardware, is to create a "work" browser profile. That runs slack and all the other work-related stuff. Nothing work-related gets connected to my personal email or phone number. At the end of the day, I close the work browser and then the only way my coworkers can reach me is via emergency means.