You are misinformed about license cost, as I’ve already explained in multiple comments.
Hard to integrate in what way? XSLT is a language focused on several things that it’s very good at but it’s not intended to replace Python or be a general purpose language. Yet there are many common data related tasks where a messy and hard to maintain pile of imperative code can be replaced with a simple XSLT.
I'm talking about the cost as being friction that resulted in 1.0 being so dominant and 2.0 being scarce.
Not everyone gets to pick and choose how they use XSLT. Place I used to work, the services team used to have a sign:
> [X] Days since last custom report
They hated it and I can't blame them, making a series of soap calls, consuming the most degenerate api ever written and generating a document for the customer was a pain. Bear in mind this was an enterprisey "do everything system", oversold by sales and the services team had to use XSLT to bridge the gap between customer expectation and what the salesman sold them.
What they needed was a host for a general purpose language, what they got was XSLT.
Hard to integrate in what way? XSLT is a language focused on several things that it’s very good at but it’s not intended to replace Python or be a general purpose language. Yet there are many common data related tasks where a messy and hard to maintain pile of imperative code can be replaced with a simple XSLT.