I bought both my parents new old machines now that they retired, and I opted for a T480 for both. They’ve been called The Last Great ThinkPad over on r/thinkpad since they are both powerful - first generation with a quad-core processor - and nicely upgradable. The upgradeability also means that you don’t have to worry overly about the amount of RAM a used model has: you can always add more cheaply (and very easily).
We have both Linux and Windows machines in my team. We do all the work in Linux, and register hours in Windows. We also all have iPhones that we only use for 2FA.