There are some very good reasons to use a Mac. Most of those have to do with the fluidity of the graphics and the intuitive nature of the OS and the Apple eco-system. Cost should not be a consideration if you are using the tool professionally; even a modest gain of 2% - 3% in productivity will easily cover the additional cost of a Mac in a couple of weeks. However, you may be more familiar with the
Windows interface (I would still give Mac a try).
Within the Adobe environment, what brand of
computer you use makes little difference. Mac M chip Multicore Intel processor (with 64-bit support) with SSE 4.2 or later or AMD Athlon 64 processor with SSE 4.2 or later. 16 GB RAM (you don't need any more for Illustrator). Plenty of storage (at least 25% of free storage available, preferably solid state).
Probably most important is to use a regular full size keyboard, mouse, and a generous desktop monitor (some people prefer two, but I find that slows me down). The ergonomics of sitting properly at a desktop will improve productivity and comfort and lead to far fewer health issues.
Some workplace environments require a
Windows OS. If tech support is provided, it shouldn't matter which brand of
computer you use as long as it meets Illustrator's recommended requirements. Make sure your tech team knows what is required (
https://helpx.adobe.com/illustrator/system-requirements.html#ai-on-the-desktop ).
Remember, you will be using Photoshop as well, likely a font management program and server, and I recommend Hot Door CADtools.