Security requires a combination of things. Only proxies that worked were VPN's and protocol guards since their job can be handled almost totally at that layer.

Security requires a combination of things. Only proxies that worked were VPN's and protocol guards since their job can be handled almost totally at that layer. Doing native or web app security only relying on that layer is asking for it unless you trust everyone you're connected to. Doesn't stop companies from doing it. The original criteria for high-assurance security, TCSEC's A1 class, said you must secure the endpoints, network connections, databases, and application-layer software. Those systems resisted penetration by NSA's hackers during evaluation. Then, there's the mainstream "security" recommendations that said use low-assurance firewalls + insecure endpoints + bandaid software on them + optionally security- or privacy-oriented proxies. This was to get the benefits of those beautiful, fast-moving, COTS OS's without investing anything in real security. It came with the detriment you mentioned among many, many others that won't go away for some time if ever.