But at the same time, do you only allow one single entity to design all planes? If another entity designs a plane, does that constitute a hostile takeover or a power grab in the aerospace industry? Surely it's healthier if multiple entities come up with their own designs and then passengers decide which plane they want to board based on their own preference.
There is no 'one single entity' in Bitcoin. Bitcoin is not ETH, therefore does not have a supreme high king. Bitcoin Core is not an entity, it's an open source software project. If you are indirectly talking about BU in this analogy, then by following it we can conclude that the plane crashed already once and all the passengers are dead (the massive exploit that crashed all the nodes, for those that don't remember or are trying to shove it under a rug).
We've clearly moved past the stage of "I think plane A has a superior technical design to plane B" and have now arrived at the "we're going to make everyone use plane A by threatening to change aviation rules to put Plane B out of business" stage, so I can't help but wonder if we still respect market freedom if we're willing to go to such lengths to enforce the status quo. I'd like to see SegWit activated, but I'd rather it wasn't at the expense of healthy competition. Moving the goalposts to obtain your goal is almost always considered poor form.
We have moved past that long ago considering that Segwit is clearly superior to EC, which is a radical and dangerous change. That said, the market is doing what the market wants. This is clearly visible by the super majority support by the users, nodes and economy (see all the signed statements either wanting to list BU as an altcoin (BTU) or in support of UASF). A vocal minority or a mining cartel is not to be in decision of what Bitcoin is or is not.