The thinking in the comments here seems very US-centric (as usual).

Until recently watching HBO in the UK and Europe was not easy unless you’re prepared to watch it on Sky (in the uk anyway) so there’s money on the table for Netflix here in the form of eating some of Sky’s share. (HBO Max is coming to EU in Jan and UK sometime next year finally)

Secondarily adding HBO gives Netflix the opportunity to upgrade its production rather than downgrade HBO.

Having access to HBO/WB catalog on Netflix is going to add a lot of value imo.

I welcome this.