In today's market, your argument doesn't hold water.

A new brand would need to start from smaller than scratch? So what? People start new companies every day.

It would require tens of millions of dollars of investment? So what? We keep being told how capital markets are just sloshing with cash looking for investment opportunities; that one of the reasons for rising inequality is due to the dearth of investment opportunities for the rich to use to seek returns.

They'd have trouble finding customers willing to give them a shot? So what? Every startup has this problem. You solve it by differentiating yourself from your incumbent competitor. When your competitor is so hated that they're getting negative press in national news outlets and state legislatures are being pressured to pass laws, your differentiation proposition is practically written for you.

I'm sure there are tractor upstarts out there trying to get funding. The question is, if they're not getting funding then why not, and why doesn't anybody know about them?

Capital markets are looking for worthwhile investment opportunities. An established ag-implements manufacturer can probably use that sort of risk capital to expand into making tractors, or something like that. Getting a large firm started "from scratch" is going to be less feasible. And these things also take their time to happen, of course.

The moment you started to see any real success with a company like this and become significant competition, John Deere would reverse their equipment-as-a-service DRM-based model, and you would be instantly crushed by their far more familiar and established brand with all the accumulated knowledge and trust people already have. It's so certain that you have essentially no chance of long-term success. John Deere can operate like this because there's no competition, but the second there is competition than can revert to how they were and you are dead, so there's no point even trying.

Brand isn't everything, it doesn't "crush" competitors in markets without winner-takes-all characteristics (i.e. network effects). People buy smartphones that aren't iPhones; people buy burgers not made by McDonald's; people rent hotel rooms not offered by Hilton or Marriott. By the time the upstarts get competitive enough to force the incumbent to act, the upstarts already have branding and market power of their own, and are not so easily crushed.

I think you discounting the brand way to much.

Hotels, Food, etc are very much Brand focused, and absolutely people have their preferred brand of Hotel and Fast Food (and despise other brands)

Manufacturing industrial equipment is a far cry from your typical ycombinator style mobile-app startup.

Imagine, they could be the next WeWork!

I like to do road trips as a hobby and I see a lot of Japanese and other Asian brand tractors in American farming areas,so there is competition

Is that really a problem in the country of the Silicon Valley? Actually, that might be the only thing preventing this from happening.