I don't follow, NAT traversal is integral to IKEv2 and pretty much "just works" [1]. Reconnecting after network downtime is not an issue either, with either on demand connection setup (auto=add) or pretty standard ifupdown scripts/networkmanager. I don't believe I had to restart my strongswan daemons in the past few months either...
I also disagree that config is 'brittle'. Quite to the contrary, I think strongswan with its exhaustive documentation and a complete test suite which provides configuration for every host in every scenario in the test suite is a great accomplishment and an incredibly useful resource [example: 2].
I think wireguard has a great niche to fill as OpenVPN replacement (which has a lot of issues) but some of its supposed benefits over ipsec are a bit overblown and a confluence of 'I couldn't be bothered to read the manual', failure to understand a difference between host-based and policy-based routing [3] and a pinch of hype-driven development.
[1] https://wiki.strongswan.org/projects/strongswan/wiki/NatTrav...
[2] https://www.strongswan.org/testing/testresults/ikev2/rw-cert...
[3] https://wiki.strongswan.org/projects/strongswan/wiki/Introdu...