Unfortunately, even though 320px iphones look to be less than IE users for us, 320px may we'll be required for a long time for WCAG (400% zoom at 1280px).
Unfortunately, I _think_ the majority of it comes down to the exchanges more-so than the data brokers.
I can't speak to exact numbers, but I believe we were quoted like 6 figures/year for JSE and I think we pay like 4 figures/year now…? Exchanges can and do charge whatever they want…so when you need realtime data explicitly, even if you skip the data brokers, you'll just have to pay. You legally cannot use data for profit from some exchanges (if I recall, JSE is one). Some exchanges seem to have a majority of their revenue coming from data licensing.
Oh, then don't get me started on ISINs and all the failed "open source" attempts to not use ISINs and how some ISINs can be used without licensing while others require it.
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My company is mostly AU/NZ (mostly because of tax, but quickly growing), so most of these data services didn't even support us until the past few years. We use a combo of like 10 data brokers to piece together coverage and we're still missing huge datasets (unfortunately Finnhub doesn't seem to cover any of them, but will look).
Luckily I focus on the Frontend/UX of our product and avoid this drama, but do feel free to reach out (contact via profile; I'm easy to find).
Good luck! I do like the idea of education, will follow. Even though I've worked in this industry for 5 years, I still find new stuff on the retail investor side of things. We'd love to educate more in our product, but we just partner with people instead..
My company pays a lot of figures for xignite and we cannot make this data publicly available without some restrictions (it would cost a lot more to do so).
My purely non-legal take is we can distribute price and metadata for instruments relative to a user's portfolio or a defined demo set of data or charts to yours, etc, but not freely distribute price data without an attribution behind it. I _suppose_ a user could add literally all 300k instruments we support to get the price data and that would violate our agreements (similar stuff has happened before, just watch it), but we'd just have to deal with the user via our TOS.
Good luck, unfortunately the next level of APIs for financial data and licensing fees can be annoying, from almost free to like 6 figures overnight. Some exchanges are much worse than others, like arbitrary pricing based on how large your company is…