Yes, but if we don't already we'll soon have our own national law requiring this data be collected.
This government aren't at all liberal in this regard and would never have been wild about trusting the EU to do this (or anything else) in the first place.
I understand that but that challenge will take years and will potentially still result in nothing happening.
Look at prisoner voting rights in the UK. The UK passed a law in 1983 saying prisoners couldn't vote. In 2001 someone mounted a legal challenge to it which was dismissed and arrived in Strasbourg later that year.
That court ruled in 2004 saying a blanket ban on prisoner voting was illegal, the UK appealed and lost in 2005. The government messed around before bringing a bill before parliament in 2009 to allow some voting rights - this bill was defeated.
And since then.... Nothing. 2014, 13 years after the original case was bought, 5 years after is was won and prisoners have no right to vote and the government have repeatedly stated they aren't going to get the right to vote.
And the UK isn't the only country where this happens - I can't remember which but either France (I think) or Italy are notorious for ignoring EU court rulings where it doesn't suit them.
EU Courts are great where the national governments feel inclined to do what they say or don't feel too strongly about it but if they don't want to do what the court says, quite simply they don't.
This government aren't at all liberal in this regard and would never have been wild about trusting the EU to do this (or anything else) in the first place.