Not only for the perceived decision of moving to, with respect, a second-rate league, but for the extortionate £177m per year salary that placed him firmly at the top of the world's highest-earning football players.
Ronaldo had his reasons for moving to Saudi Arabia
"In Europe, my work is done; I won everything, I played at the most important clubs in Europe and for me now, it's a new challenge," the Portuguese footballing legend said at the time.
"This is a great opportunity. Nobody knows this but I had many opportunities in Europe, many clubs in Brazil, in Australia, in the US and even in Portugal.
"Many clubs tried to sign me but I gave my word to this club to develop not only the football but other parts of this amazing country."
Whether those listening were assuaged by the narrative is a moot point.
Some two and a half years after uttering those words, football in Saudi Arabia has certainly seen an uplift in the type of player moving to that part of the Middle East, and that has to be down to Ronaldo's influence.
Ivan Toney, Riyad Mahrez, Yannick Carrasco, Fabinho, Jhon Duran, N'Golo Kante, Roberto Firmino and Karim Benzema are just a handful of other big names that now ply their trade in a league which, whilst there has been improvement in terms of recruitment and level of professionalism, is still some way off of being able to be compared with some of the best in the world.
How have things worked out for Cristiano?
To that end, Cristiano can certainly be said to have been something of a trailblazer, but how have things panned out for the player and, more generally, for his club, Al Nassr, since his arrival?
From a personal perspective, 72 goals (and 16 assists) in 74 games is an incredible return. Even if the quality of opponent is negligible compared to those whom the Portuguese captain has played against throughout his stellar career, Ronaldo's age has to be factored in.
Ask yourself... how many 40-year-old players do you know who are still scoring at the rate of a goal a game?!
His current shooting accuracy of 62.9% - 61 of his 97 total shots so far this season have been on target - is a vast improvement from when he first joined Al Nassr, and a 75.5% pass completion stat is also better than his first season and a half at the club.
Defence was never his strong point, so 16 tackles attempted and just six won in two and a half seasons isn't really a surprise, nor should it be used against Ronaldo to belittle him.
Perhaps the only real issue for the player and Al Nassr is that they've not gone on to win the Saudi Pro League since Ronaldo's arrival, and that has to have been in everyone's thinking when handing out that impressive contract.
Still no Saudi Pro League title for Ronaldo
Al Hilal have been the most successful team in the region for years, and it's they who Ronaldo et al needed to topple from their perch.
The status quo had remained the same as pre-Cristiano until recently, but it's Benzema's Al Ittihad that are now in the box seat for the title.
At the time of writing, Al Ittihad top the SPL on 68 points with five games of the season left to play. The first of those is on Wednesday night against Ronaldo's Al Nassr, who themselves have an outside chance of the title if they win, as it would bring them to within five points of the leaders with four games to go.
Former Real Madrid strike partner Benzema might have something to say about that, as he too has spearheaded his side in attack with 18 goals and nine assists in 26 games this season.
Al Hilal's fixture against bottom-of-the-table Al Raed should see them close the gap on Al Ittihad if the latter can't overcome Al Nassr, and that would set things up nicely for the final few games of the campaign.
Ultimately, Ronaldo's time at the club is likely to be judged on trophies won, and no SPL title since 2018/19, well before the Portuguese's move, clearly isn't good enough.
Lasting legacy means more than individual brilliance and a handful of positive results
Two second-place finishes in the last two seasons has seen Al Nassr go close, and the Portuguese has also broken the record for most goals in an SPL campaign.
The history books will, however, show them as runners-up despite a further significant financial outlay on players such as Sadio Mane, Marcelo Brozovic, Aymeric Laporte, Otavio, Alex Telles and Seko Fofana.
Al Nassr weren't able to triumph in the 2023/24 AFC Champions League, losing to Al Ain in the quarter-finals. They only made it as far as the Saudi Super Cup semi-finals in the same season and also lost the King's Cup on penalties.
Ronaldo's two goals against Al Hilal in the 2023 Arab Club Champions Cup final at least saw them win that title, with the 40-year-old also bagging the Golden Boot in the tournament, though arguably that's just a modicum of success which isn't really acceptable at this stage.
When you talk seriously about leaving a lasting legacy, only delivering a handful of good results to get everyone sitting up and taking notice doesn't really cut it.
Notwithstanding Cristiano's place in the history of the game thanks to his exploits and Man United and Real Madrid in particular, will he really want to be remembered in Saudi Arabia as the player who started the gold rush and continued to elevate his personal brand, but wasn't able to alter the status quo both at his club and in the region as a whole?
