>>75cybercrime causes billions of dollars in damages every year, and you, posting on a low-traffic textboard, claim to know the solution
if you really knew a solution, you should try to profit off it
or, more likely, you're just talking out of your ass, and security is a little more complicated than mere dependent types, because you don't know shit about infosec
will dependent types stop someone from clicking on a link? will it stop SQL injection? will it stop word docs/maldocs/macros? will it stop JS embedded in PDFS? will it stop ransomware? will it stop cryptojacking? will it stop keylogging? will it stop RATs? will it stop XML external entity attacks? will it stop reflected XSS? DOM XSS? CSRF? remote file inclusion? local file inclusion? billion laughs? UDP reflection? UDP amplification? NTP reflection? default passwords? overflows? numeric underflows? slowloris resource exhaustion? predictable session tokens? predictable resource location? sybil attacks? hash cracking? social engineering? covert channels? data exfiltration? privilege escalation? reverse shells? steganography? file descriptor attacks? vlan hopping? arp spoofing? shatter attacks? SSRF attacks? cache poisoning? DNS hijacking? DHT poisoning? CTS flooding? smurf attacks? fraggle attacks? format string vulnerabilities? array indexing errors? mismatched array new/delete? stack overrun? unused values? file handle leaks? OSINT/opsec issues? predictable TOTP? dns exfiltration? exfil via x.509 metadata fields? content-type header injection? WMI hijacking? UEFI rootkits? network resource leaks? debug features left on in production? compiler backdoors? ephemeral netcat backdoors? hardware backdoors? side channel analysis? rowhammer bit-flipping? van eck phreaking? null pointer dereferencing? uninitialized/improperly initialized memory? lack of proper ASLR? checksum collisions? port knocking? clickjacking? DNS sinkholing? remote code execution? VM escapes? missing lower bounds? iterator invalidation of mutable data structures leading to undefined behavior? data inferrence? misconfiguration? directory enumeration? unhandled return codes? hooking? return pointers to local variables? invalid use of negative values? passing large parameters by value? underallocations of dynamic data? nop sleds? heap spraying? heap pointer replacement? JIT spraying? race conditions?
there are hundreds and hundreds of other attack vectors I know about that I could post but it's late and I'm drinking and need to fall asleep soon