My interests are skewed a bit because I'm not interested in the traditional install - not even frugal if I can help it. Doubly weird because I like a clean garage, and have dumped all my vintage antique computers - starting with MicroVax, for modern, yet modest new gear.
I like running solely with usb sticks for boot and for data. Similar to how I loved running live from CD. And sure, with Juanito's excellent instructions, I've built many uefi-only sticks with additional tools, manual partitioning, formatting, grub'ing and so forth, simply because the existing iso does not support uefi-only. New stick - rinse and repeat. Pull out the notes each time because it's not finger-memory.
Ok, that's cool. So now with modern uefi-only machines that I use, and inherent slacker character, I look for the easier way to remember on how to get TC up and running within a minute. Multibooters help me achieve that, even if I'm only booting up TC all by itself.
The really cool thing about Ventoy, is that it can relieve the devs from having to think about providing secure-boot shims or any of that nonsense in the iso. They can concentrate on what they do best, and leave all that modern boot stuff to other devs that concentrate mostly on that aspect. Ie, I can boot TC on a fully locked down Secure-Boot system if I want. (Not that I want to, I usually disable it, but it's possible).
Or I hate to say it, the multibooter front-end can unjam a possible release-blocker due to political / personal reasons, and the user can decide. Nothing insinuated here with TC, it's just a matter of insurance for the future.
I kind of look at TC like I would as an embedded device maker, with out of the norm requirements, but come he** or high-water, I'm going to get that iso to run!