This seems like the perfect opportunity to introduce those unfamiliar to Robert Elder. He makes cool YouTube[0] and blog content[1] and has a series on regular expressions[2] and does some quite deep dives into the differing behaviour of the different tools that implement the various versions.
His latest on the topic is cool too: https://www.youtube.com/watch?v=ys7yUyyQA-Y
He's has quite a lot of content that HN folks might be interested in I think, like the reality and woes of consulting[3]
[0] https://www.youtube.com/@RobertElderSoftware
[1] https://blog.robertelder.org/
[2] https://blog.robertelder.org/regular-expressions/
[3] https://www.youtube.com/watch?v=cK87ktENPrI