I would offer to Andrew that security does not have any 'magic key' and the only real security is continual vigilance and education. In other words; 'it's not your car key that keeps your car from being stolen by someone with a tow truck'.
I would also note that most forklift related companies do not have anywhere near the need for security that a bank does, and all the banks I know of allow access via personally owned phones and computers.
Since, in the USA and most of the "free" world, security professionals are not permitted to openly discuss failures and shortcomings in products that have "closed source" [trade secret] protections, there is almost always some less than perfect 'back door' (?NSA access?) that can be exploited by those wishing to use the back door, in those types of products. You can do a search for "MSwindows {closed source} -vs- Linux {open source} security" to get a better idea of what I am talking about, if anyone cares.
IMNSHO, Proper employee education and motivation is far more valuable in security, than who owns the devices. It's just no where near as easy to do correctly.
I agree completely with Andrew's bottom line of; "Better to have company equipment standardized and monitored", for a whole lot of reasons.