You're right that there are definitely opportunities for improvement here. As a Product person that has worked in EMR/Healthcare IT systems, I can tell you the biggest challenge is most of the decisions are driven by legally-required compliance. In many cases, you literally cannot make it better because the brokenness is /by design/ to comply with the law.
Nearly across the board, especially in the US, our legal and regulatory climate has not kept up with technology and often actively works to the detriment of technical innovation and improving our systems.
Systems that nobody has ever asked us to use. Entire APIs with full access to key data, that nobody uses.
Keep in mind, the boomers are retiring and there aren't enough Gen X to replace them. Here's the graph of job postings for my specialty (takes a bit of finagling for it to render, esp. mobile, but suffice to say the system is going bonkers): https://www.pathologyoutlines.com/jobs?jbl=1
Shared system resources (e.g., registers, main memory, secondary storage) are released back to the system, protected from disclosure to other systems/applications/users, and users cannot intentionally or unintentionally access information remnants.
Doctors and hospitals are not necessarily aligned groups (either with each other or with nurses) on the issues, and private insurers, state governments (as market participants themselves, via operating public insurers such as Medicaid agencies), and other players are also very powerful lobbies.
It's like asking why most software devs don't go to bat for technical support people.
