Hhmm I don't remember it being that slow, but then again, I didn't need much throughput for my use cases. Frankly, I'm surprised that Zerotier and Tailscale are that slow as well, so I'm not sure how trustworthy that article is.
I found this other benchmark[1] that places them much closer to native WG performance, with Netmaker still in the lead, and somehow faster than a direct connection. This is probably due more to Netmaker using the in-kernel WG, instead of the userspace implementation. I'm kind of curious to give it a try, TBH. :)
Hell, even OpenVPN is _much_ faster than that[2,3].
Also, yeah, tinc development has been slow for years now, but I didn't experience any issues with the prerelease versions. It's certainly behind the times now, but I also enjoyed how easy it was to configure and use.
[1]: https://techoverflow.net/2022/08/19/iperf-benchmark-of-zerot...
[2]: https://www.zerotier.com/blog/benchmarking-zerotier-vs-openv...