You have to have the political education of a 5 year old to claim that the far right and the far left are similar. Even centrists think the theory is horseshit:

Given the basic implausibility of the horseshoe theory, why do so many centrist commentators insist on perpetuating it? The likely answer is that it allows those in the centre to discredit the left while disavowing their own complicity with the far right. Historically, it has been “centrist” liberals – in Spain, Chile, Brazil, and in many other countries – who have helped the far right to power, usually because they would rather have had a fascist in power than a socialist.