This is irrelevant. Your statement was "Nintendo notoriously cheaps out on RAM." Not "Nintendo's machines are generally specced lower than their counterparts."
The logic is that Nintendo releases low power devices, as you say. So to compare a Nintendo device to it's competitors, then weirdly single out the RAM, say it's less than the competitors, and totally ignore the rest of the hardware design isn't a valid way to decide if the amount of RAM is low. If Nintendo cheaps out on RAM specifically then we would expect to see less RAM in their machines relative to the rest of the speccs. We do not.
When Switch came out it was a mobile device with more RAM than the high end iPhone and comparable RAM to the high end Samsung device.
The Wii U had a GPU that was roughly the same class as a low end Radeon that shipped with half a gig of RAM, and the Wii U had 4 times that.
The Wii used an overclocked GameCube GPU, but gave it 8x the amount of dedicated graphics RAM.
These are not hardware designs that are RAM limited. Their limitations are elsewhere, so much so that a generous increase in RAM would not see significantly increased performance. The thing that Nintendo is actually notorious for is using excess RAM to overcome to limitations of their underpowered GPUs.
We know that Drake's performance profile puts it in the neighborhood of the PS4. Nintendo's pattern has been to land in last gen's power area, then add RAM to that to cover the gap. Which would be 12GB.
Do I expect 12GB? No. 8GB is perfectly fine.
Does Nintendo cheap out on RAM specifically? No.
You cannot give every single aspect of hardware specs the same level of importance, you can't say hardware A is 4x times more powerful than B in Y, so it should be exactly 4x more powerful in Z.
Having half the RAM is a bigger deal-breaker for ports than having half the GPU power. I expect anyone who has played games on a PC to know that, or anyone who has played third party games on Nintendo consoles, and have an understanding to why they are so much worse than elsewhere, or why they don't come at all.
A mid range PC can have the same amount of RAM as a higher end PC, but cheaping out on other aspects, because RAM is a much more determining force.
Nintendo could've easily put 8 GB on Switch, Nintendo is not Sony, they don't need to count every penny, they could afford to have a smaller profit margin to provide a much better experience, for relative cheap cost for such a rich company. They were most probably told do so by third parties. The fact that the hardware is weaker overall, should only encourage them to at least match or even overdeliver on the RAM side, like the SteamDeck does. The fact that the SteamDeck overdelivers on RAM, will give the hardware a longer life-cycle when it comes to Gen 9 ports, to compensate for the hardware's lack of GPU power compared to Gen 9 machines. Nintendo didn't and it severely hurt hundreds of games on Switch. Same thing can be said about the Wii U and 3DS, with the 3DS, Nintendo was hugely hurt for being too greedy on the hardware profitability, Reggie warned Iwata. At the end they had to correct themselves by doing a big price cut, and releasing a new model, that had oh look at that, much more RAM.
Comparison to smartphones obviously don't make any sense. Is an iPhone aiming to run The Witcher 3? No. Is it aiming to have a top camera? Yes. They don't need lots of RAM, they need other things, and it's also a completely different business with completely different profit strategies that cannot at all be compared.
So did Nintendo cheap out on RAM on their past systems? They absolutely did, that's a fact, the New 3DS is an example where they themselves basiclaly admitted it with their actions. Having more RAM would have hugely helped their systems, and Nintendo could absolutely afford it.
They didn't because they are pragmatic and don't necessarily want to provide the absolute best experience for their fans, Nintendo is all about "good enough". And like I said before, the results show that to most of their audience, they are right about cheaping out, but they are doing it.