> it's just a portal that gives the news
A portal? Bloomberg News has its very own reporters (and jourobots). They investigate and write original content. People usually don't buy the terminal (~2000 USD/month) only for that, but if they do, they can read everything directly in the terminal.
> What I don't get is why have a custom monitor, keyboard?
The monitor is, these days, only about branding. Ten to fifteen years ago, Bloomberg offered good-quality LCD screens with integrated mounting arms for 2 or 4, at a time when that was a pretty high-end setup. As LCD screens became cheap and ubiquitous, many users don't have the Bloomberg ones, but they still have the Bloomberg keyboard. It's useful because it has special labels for a few hotkeys, plus some of them have extras like fingerprint readers. If you lack the special keyboard you can press Alt+K on any keyboard and the terminal will show you a graphic of the special keys for reference.
But to really understand why they have a special keyboard, you need to look back a good long while. That's covered here: https://www.fastcompany.com/3051883/behind-the-brand/the-blo... - the gist is that a "Bloomberg terminal" used to be a real terminal, connected to a magic box on the customer premises (which served several terminals). There have been many, many iterations of the terminal hardware, from a dedicated proprietary box, to software running on Sparc workstations, to software running on Windows, with the keyboard becoming more like a PC keyboard around the turn of the century.
> is it a VPN
No. Traditionally, customers connect their terminals back to the Bloomberg service via leased lines (i.e. not the internet). But for many years now you have the option of using the internet, though not everyone wants that.
> The cost of the product is ridiculous.
The cost of the product is much less than what some customers would be willing to pay. Most customers pay about the same monthly fee, regardless of where they are in the world, regardless of their corporate income statement, etc. So yes, it seems expensive to people who wouldn't get that much out of it. Some schools get a discount.
> Is there a cheaper alternative that does not require specialised hardware?
Bloomberg does not require specialized hardware at all. You can install it on any Windows laptop, and you are more than welcome to do so. As for cheaper--yes, there are lots of things which are cheaper, but you will be hard-pressed to find any combination of those which is still cheaper and yet does most of what Bloomberg does (i.e. has similar quantity and quality of data, and applications built up).
> I know Bloomberg is a politician
He is now, but he was not when his company went from 0 users to 100,000 users.