If Ronaldo wins the Ballon D'or this year as expected he'll go ahead of Messi in Ballon D'ors for the first time in 10 years, last time he was ahead was in 2008 when he went 1-0 up. Leo needs to win the CL this season to level it at 6-6 in 2019 hopefully.
It pisses me off how it's now extremely unlikely that Messi will go down as being the undisputedly best player of his generation. There's been so many missed opportunities when Messi has seemed so far ahead but Ronaldo has always come back.
I and most football supporters will still think Messi is better but it's now gotten close enough that it's become more subjective as opposed to when it used to be a clear fact. Unless Messi wins a WC, dominates Copa America, or leads Barca to at least 1-2 more CLs, that probably won't change.
In terms of missed opportunities:
1(2013) Messi had dominated CR 09-12 and won the previous 4 BDO. Madrid were also in turmoil under Mouyes with CR apparently wanting out. Unfortunately, Messi then has a few injury problems and underwhelming performances which allows CR to make Messi/Ronaldo a debate again and win BDO.
2 (2014 WC Final) This would have guaranteed Messi 2014 BDO, ended comparisons with Ronaldo, and put him on Maradona/Pele terms at international level. Instead, he doesn't play particularly well, misses golden chance, Argentina loses.
3 (Early 2016) Messi and Barca had dominated 2015 while Madrid/CR seemed streets behind. CR looked in serious decline while Barca and Messi looked unstoppable. Instead, Messi/Barca shits the bed against Atletico, Messi loses another INT final, while Ronaldo manages to lead/fluke his way to CL and Euros.
4(Early 2018) Ronaldo had a shit start to the season and looked finished at the top while Messi was miles ahead. We all know how last 6 months have gone and now CR is BDO favorite again