Perhaps switching perspectives a bit might help you to understand it?

I know rationally that 1lb ≃ 1/2 kg. But if you tell me "I bought 5 lb taters" I'm not picturing anything until I mentally convert "5 lb ≃ 2 1/2 kg, that's a lot". And if I don't do this mental conversion, "5 lb" means the same as "7 diddly-doodly" or "half a skwerl", nothing.

I also know, rationally, that 1 ft = 1/3 m. But if you told me "I'm 10 ft tall" I'd be like "okay... [small pause] wait, isn't this around 3.3m tall? That's bullshit, nobody is 3m tall".

From the above, following the exact same reasoning you've been trying to apply here, the conclusion is the opposite as yours: while the metric system would allow you to intuitively grasp how large/small things are, the imperial system doesn't. And if the same reasoning leads to contradictory conclusions then the reasoning is bullshit.

What would explain the above is the following:

• any measurement system allows you to intuitively grasp how large/small things are, once you're used to it
• You are not used to the metric system, even if trying to fool yourself with "I can seamlessly shift between systems".
• I'm not used to the imperial system. But unlike you I can tell apart what's my own habits vs. what's from the system itself.

And really, this shit is like QWERTY keyboards. I'm happy with mine, and I can instinctively find the keys without looking. But that doesn't automatically stop QWERTY from being an awkward mess of a layout, and anyone arguing "QWERTY is more intuitive" is full of shit.

And you, by your examples, are STILL using a device to measure things because the metric system isn’t that intuitive.

Following this dumb "ackshyually your using a measurement device lol, you're hand lmao", you're also using a pair of measurement devices: your eyes.

But let's roll with it. The reason I still need to use a "device" has zero to do with the measurement system. It's profession; I'm no carpenter, my work never trained me to bat an eye at something and say "this should be twenty five large". This is not about the measurement system itself.

I can tell a 4 year old child to cut a piece of paper in half and they intuitively understand about how much that is with no pre-measured body parts.

A 4yo can do the same with metric.

You're confusing "fractions vs. decimal" with "imperial vs. metric", and making a fool of yourself.

Dunno if you noticed, but I actually used fractions with the metric system in this very comment. The reason people don't do this too often is because fractions are awkward to add and subtract, and you're giving up unit conversions. But you can. Half a kilo, a third of a metre, it's fine.

In the meantime, if you were to seriously use decimals with the imperial system, you'd reinvent the metric system poorly. "This is 3.62ft large... okay, it's 362 centifeet".