I think its two big reasons. One, the thing you're selling is often negotiated. So company A might buy X, Y, and Z from you, and company B might buy X and M from you. They can and do ask software vendors to customize software to the point of it no longer being an apples to apples comparison. They also negotiate service times, contract length, contract language, legal penalties, all sorts of things that make big companies different than consumers.
The other big reason is that some enterprise vendors still price things in an "old school," pre-internet way. That's my term for giving different companies the exact same thing at a different price. For example, you might sell your software to BigFruitComputer Company at $100 per user and to the small consulting company at $10 per user. In fact, you charge your users whatever your salespeople can negotiate, which is why they're still around and making money. The company getting charged more doesn't complain because companies don't generally disclose what they're paying for all their different things to each other and so they don't know. This would be practically heresy in the consumer world and frowned upon sometimes as dirty. You shouldn't charge a little old lady more because you can convince her she needs features "just in case." But it seems acceptable to charge a company more because your salesperson can convince them they need something, even if they don't.
If you're looking to disrupt the enterprise market, I suggest keeping in mind a few things.
One, small businesses are like consumers. They know they don't have much power to negotiate and don't often expect so. So have a consumer-like pricing plan that appeals to what they want, prices it in a way that gets it for them cheaper than they're currently getting, and lets them do it in a no-hassle manner.
Two, big businesses have budgets and levels. The person browsing your website might not be the person buying your software. That sounds weird right? But true. So the tech guy who says "wow, your software will save me so much time" doesn't know how much the company currently pays for such software, because he didn't negotiate the contract and isn't privy to that sort of thing. The executive who did negotiate isn't probably browsing your website. You now have a sales problem, which is why salespeople are still around.
The best way to disrupt such a market, if you're interested in doing it, is to find out what big companies pay for what you're giving them, and make it a lot cheaper. Whether its cheaper in price, or cheaper to the company because your software works better and saves them time or for some other reason, doesn't matter. THEN, market from the top down and the bottom up. Give talking points to the tech guys or whoever is on the bottom. "This will save you time," or "it will be easier," it will do X, Y, and Z and solve problems O and P. Show them how this saves the company money and give them ammunition to use in the next meeting. THEN ALSO target the executives, but without technical talking points. "Does your company pay more than $200 per user for X services? We can offer it for $100! Cut costs 50%!" and so on. Make it all about the bottom line, the executive will look better, you get a sale.
So, that was a long-winded way to answer you question "if I were to be trying to enter and disrupt some enterprise software market, am I losing anything by trying to show more of what the actual product does and how it works?
The answer is no, not really, but you're not gaining much for the effort either. Sales in the enterprise market aren't made on screenshots. They're made by being a salesperson and appealing to all the stakeholders. Screenshots are a tiny afterthought and won't disrupt anything. You still need people to buy your products and the person on your website looking at the screenshot isn't that person.