Is this a defensive move, against AI taking over the stock image market?

Both of them already provide AI image generation themselves.

https://www.shutterstock.com/ai-image-generator

https://www.gettyimages.com/ai/generation/about

if you're going to get scraped anyway, might as well get paid

Not sure it'll help against AI eventually taking over. They can't compete on price, and the quality ceiling for "generic corporate announcement picture of diverse people smiling" is very reachable for the current gen AI.

Just don't show the hands of those people

I would also consider consolidation as move to cut costs. If there is no more growth or it is taken by AI, that is the next step to get line go up.

The defensive move here is the sellers cashing out while they still have a decent valuation and taking their money elsewhere.

Probably the plan is to sue big, and convince investors that's going to work.