Of the 10 teams that compete in the qualifiers, I can say that perhaps only Bolivia and Venezuela are far below normal and would have difficulties competing in a world cup.
The top tier teams are the 3 obvious ones: Brazil, Argentina and Uruguay.
The national teams of Chile, Ecuador, Paraguay, Colombia and Peru are teams that play the world cup regularly (not like the top 3), but all these countries have good players that play in the European leagues and a good team.
So if the 7 Conmebol teams qualify for the 2026 World Cup, you can be sure that they will be competitive teams and with good conditions to play at the same level of the second tier of European tems for example.
I believe that for 2026 those who will miss out will be Bolivia, Venezuela and Paraguay.
With the exception of those two teams, european soccer is much ahead in skills and strategies. Nonetheless, Europe is exporting many coaches to run national teams in another continents. Even Brazil was looking for a foreigner to train the national team after the fiasco against Croatia last year.
Regarding the south American teams, we cannot be sure to say if Argentina and brazil are the only good teams that perform well in the world cup because we know according to some news and according to what their coach said Messi is going to play for Argentina in next world cup in 2026 but can't be a reason to say the other teams will not show good performance, from the last world cup and what we saw in Morocco teams I can say each south American teams can have the chance to perform much better than Argentina or brazil in the next world cup.