What do you mean it’s not worth it? If you use the company’s computer it’s on them to handle all the liability. If you use your own computer then you’re now on the hook. It is 100% worth it to use the company-provided computer.
Is your company not providing you a computer? It’s up to them to manage that risk.
I obviously know nothing about your business but this sounds like a mistake from an outsider’s perspective. Enterprise software exists so companies can call somebody and get help when something goes wrong. Also more people are familiar with Windows and Microsoft Office so it’s much easier to onboard new employees and find IT Administrators who can support their environment and keep things running smoothly.
I think the setup you’re describing will cost more in the long run because your company will have to find people with more specialized knowledge to help maintain everything.
I love Linux and open source software but I also think they should only be used when they fit the need.
That’s not on you. I would communicate with management and illustrate that you can’t do your job without a proper computer. If they refuse to help, get it in writing. You should not be held accountable.