The questions which arise from this conclusion are;
1) What can the Church do about this?
2) Who (if anyone) is actually the true Pope?
3) When a formal heretic ascends to the Chair of Peter, what does this tell us about the times through which we're living?
2) is easy.
Benedict.
The Church has survived many bad Popes in our history.
This Pope has not uttered these errors ‘Ex Cathedra’.
So, we retain the formal church doctrine and pray for God’s Grace.
I am correctable, but I know of no modern mechanism to remove a heretic pope.
In the past, councils had the power, but with the victory of papal supremacy, that is no long possible.
A work around would be to say “He is not a Pope any more since he said X”. However, who has the power to say THAT!