WireGuard vs IPSec/IKEv2
While IKEv2/IPsec could rival OpenVPN in several areas — offering better speeds and lower CPU-usage, for example — this older protocol really can’t compete with WireGuard.
WireGuard is faster than IKEv2/IPsec, offers stronger encryption, and uses a far smaller codebase. For most users, WireGuard will always be a better option.
IKEv2/IPsec might be your preferred option if you want to run legacy encryption methods. WireGuard supports a more limited selection of modern encryption processes. However, the majority of people looking for a VPN will be wanting the most up-to-date encryption possible, and on that parameter WireGuard wins.