The VDI angle makes the most sense out of all the answers I've seen. However, I can't imagine anyone concerned about security would do BYOD for laptops or desktops.
Every person I've ever seen using VDI has a company PC plus a virtual desktop, so there's no cost savings there. The main advantages I can see are easier backups and not having to worry about network bandwidth too much (just enough for RDP is good), but there are drawbacks too like dealing with remote printing, a lack of support for hardware security tokens, etc..
For example, try to get a YubiKey working [1] with WebAuthN or FIDO when using RDP / VDI. It's basically impossible and you're stuck with crappy 2FA like TOTP.