Interestingly, it is disabled by default for me.

Reading the github blog post "If you previously opted out of the setting allowing GitHub to collect this data for product improvements, your preference has been retained—your choice is preserved, and your data will not be used for training unless you opt in."

I guess we have to check out again on April 24 ?

Me too, which is making me wonder if they're planning on silently flipping this setting on April 24th (making it impossible to opt out in advance).

We are not. The reason we wanted to announce early was so that folks had plenty of time to opt-out now. We've also added the opt-out setting even if you don't use Copilot so that you can opt-out now before you forget and then if you decide to use Copilot in the future it will remember your preference.

Is it because I'm in the EU?

I'm in the US and it's off for me. I believe I've previously opted out of everything copilot related in the past if there was anything.

I'm in Canada, so not only the EU at least.