I thought you'd say that.
In your eyes, party democracy can be ignored or sidelined if the end goal is a public facing party you would consider to me more electable.
Leaving aside the fact that I don't really see any evidence of a centrist party being more electable (as we will go round in circles debating hypotheticals on that forever), my main problem with that view is that it's a slippery slope.
You sideline the CLPs you don't agree with to push through an unpopular policy platform; you change the leadership rules to give more control to the PLP and less to members; you cause thousands of members to leave, unions to unaffiliate and try to make up their contributions with corporate donations; you alienate (or make redundant) the grassroots activist campaigners and focus on being so unthreatening to established power that you'll get to use their media apparatus to sell your message.
At a certain point you cease being a democratic party for workers trying to mobilise against an unjust status quo and just become a more apologetic liberal polite version of the Tories. Then since we're under FPTP you go back to the pre-Trump American system where Labour play the role of the US Democrats as a different face of the same singular business party.
You could argue that's what the Labour party has always been, and to a certain extent I would agree. They've not really been a socialist party since 1951 and haven't been a social democratic party since 1976 (aside from a brief period under Corbyn). Nevertheless when we're facing the sort of incredible challenges that the world does today, the idea of the only viable alternative to perpetual Conservative rule being a more woke business party just isn't good enough for me.