none of this has anything to do with substack making a business plan off of sucking down twitter data and advertising on twitter. There's no reason twitter has to put up with that.
if you want to believe not directly contributing to competition that tried to take your data and advertise on your platform is fragile, thats of course your choice. To everyone else its just common sense. the fragility is the business plan that needs to steal its competitors data and space for advertising to have a hope in succeeding.