ROS1 is primarily used with linux unless you use a VM. ROS2 can be used on linux, mac or windows. You can also check out AWS robomaker to use ROS in the cloud.
FWIW, I tried using Ros on Windows as recently as the summer but IMO the biggest issue is that 3rd party packages like those listed on the Github repo are predominantly coded for Linux. So I'd have issues with builds failing to compile if they weren't tuned to work on Windows.
I ended up just installing Ubuntu and dual booting to save me a lot of hassle.
Why haven't I tried ROS on Windows? I never really had the need to, I primarily use Linux at home and work.
I did briefly evaluate ROS 2 (ardent) on Windows at my previous job. It seemed to work fairly well, I built it natively, ran the demos and did some latency/throughput comparisons between DDS implementations.
While ROS2 promises windows compatibility I’m not so sure how it will turn out. Most guides, drivers and general support will focus on Linux. We’ll see how wrong I am when ROS2 finally takes off!
You can hit Amazon with niche categories. For example they have shoes and clothing, but there is no "Amazon for nurses scrubs or school uniforms" or other niche categories. They also do not serve many countries (e.g. Philippines). A startup that served these needs would not have Amazon as a competitor at all.
Out of curiosity, I just searched Amazon for "school uniforms" and there's a lot of stuff there. (Makes sense, since there are millions of kids in private and parochial schools - it's a big market.)
Even if you manage to find a retail category that Amazon is not currently involved in, you might wake up tomorrow to find that they've suddenly become your competitor.
You have found a category that Anazon serves, but does not serve well. I buy nearly everything on Amazon but I still have to buy her uniforms in person (each school has a specific color scheme, plaid pattern, collar style, etc.). My wife still buys her nurse scrubs from a guy who comes around the hospital and only takes cash. These are things you just can't get easily on Amazon, even though it looks like they have that category covered.
Also, you could compete with Amazon on any category just by having a bigger selection of same day delivery in some niche.