Because I don’t want my work to be able to literally watch and record every keystroke and mouse-click I make. Much less listen or watch me at home by activating the mic or camera. There’s no way I’m using that compromised device at home regularly.

I have a work laptop I only rarely use for just one very specific thing that I can only do on that laptop. I also have my personal laptop where I do everything including my work and if I want to sidebrowse stuff then I open up a different browser—all of which are privacy-hardened.

I just recently got a new laptop so now I have one that is even more locked down, secure, Linux-based, and I only use it for personal stuff.

Depending on where you work, your employer may be able to take that personal device you’re using for work in the event of a lawsuit against the company (where they need to retain anything that may be relevant to discovery), or in the event of a security incident (where they may need it for forensics).

I work in information security, and I practice strict isolation for that exact reason. Two laptops, two phones, because if anything ever happens they can and will take devices for analysis or evidence. If you are using an issued device, they’ll assign you a new one; if it’s a personal device you’ll get it back when they’re done with it, which could take years.