Istio is really quite interesting of a project it promises everything, has a lot of frequent new engineering solutions, and then people have to hire consultants to make them be able to do a fraction of that. Itβs the SAP of the kubernetes world.
If you try to use every single feature of Istio, sure. If you just need encryption it's not that bad. And it looks to be getting better (no more sidecars, eventually).
Regarding Cilium, there's a backup plan as soon as there's a license change, which would be a herald of things to come:
the fork.