Churchill was the right man at the right time for the UK during WW 2.
But he sure did make his share of major mistakes. For example, Churchill was heavily involved in the planning for the disastrous Gallipoli campaign during WW 1.
And his dealing with Stalin were often naive. As WW 2 was ending Churchill and Stalin made a secret agreement on how to divide Eastern Europe into “spheres of influence”. For example, the UK was to get something like 20% influence in Hungary. Who is his right mind would think Stalin would honor that?
https://en.wikipedia.org/wiki/Percentages_agreement
All good points, but on the only situation that is reasonably analogous to the present, he is thought to have been the most insightful thinker, proven prophetic in the 1930’s by events of 1939 and on.