Final answer:
PPTP is becoming obsolete due to security vulnerabilities and the availability of more secure VPN protocols like OpenVPN, IPsec, and WireGuard.
Step-by-step explanation:
PPTP (Point-to-Point Tunneling Protocol) is becoming obsolete due to security vulnerabilities. One of the reasons is the availability of more secure and advanced VPN protocols like OpenVPN, IPsec, and WireGuard which offer better encryption and authentication.