I've said repeatedly it's about modern society in general

They're both very relevant, maybe Katy is still better known on a worldwide scale, but still both are super famous.

Is the OP on drugs? Modern society? What a clown

Katy has toured in South America twice and in more European cities than Taylor ever did, so there's that.

Next era I am sure Taylor will finally tour more continents I'm sure

How do their overall tour sales compare?

slaughtered so far

Currently it's Taylor who is mid-era. Will be Katy during her era.

Since we're talking about relevancy and not about success, the answer is Katy WW (not sure about the US)
Like no one older than 30 knows either of them here in my country, but it's much more probable to find someone who knows Katy than Taylor. And teens/young adults like Katy more (talking about the people I know).

The top artist from the Forbes list.

It's not about hard numbers only, it's about expanding your brand. Taylor will always gather a big crowd in Nashville and New Orleans but hasn't ever set foot in Sao Paulo or Mexico City.

So Taylor makes more money than Katy with less locations? Sounds like she's more relevant to me

Taylor Swift

Single sales
Alber sales
Tour gross
Acclaim

Obviously Taylor. She's more relevant than all of our favs at the moment I think.