It does not matter how much you like or prefer one candidate over another if they aren't electable by the country at large.
It isn't 'power at any cost' but what it will take to actually win that majority. There is no prize for coming 2nd.
This is applicable to BernieBros in the USA and Corbyn & Long-Bailey supporters in the UK. Those candidates scare off major tracts of the electorate, both nationally and locally.