Yeah I know that it has no bearing on who's the best - just giving some reasoning for why he didn't leave Spurs earlier. Plus, he probably (mistakenly) thought Spurs could take the next step. He is a great guy it seems but he doesn't seem the smartest off the pitch. Levy probably convinced him for years, spun him lies about how Spurs could conquer Europe. I believe Mourinho does similar in that All or Nothing documentary series.
He truly is a great player. The problem is he's 33 by the time the World Cup ends and next season starts. As good as he is - and he doesn't rely on pace and doesn't seem too bad with injury record these days - it's always risky to buy someone that age. If he was the same age as Haaland and performing as he is now, I'd say every club in Europe should desire him. But how long does he really have left at the level he's at? Maybe 36 at most? That's three years. I am sure he will be a good player still after that but this level he's at is impossible almost for anyone to maintain past 35 or 36.
In all honesty, him going to Barca would never happen for many reasons. But in a hypothetical world, I'd be looking more long-term and trying to find a gem or prime player aged 26-27 (like Osimhen as many want, as an option). He's not as good as Kane for me, not by a long chalk (though he is very good), but he is the right age profile, and as Tempt and others said, brings a physicality and power and raw aggression that Barca could use in a number 9.
