Some of the handheld gamers bought or were going to buy the original Switch, others wouldn't for different reasons (too clunky on the go, waste of money for features they don't want/need). We don't know which of these two groups are the majority.
Most price conscious people who set themselves a budget for buying a Switch (for themselves or as a gift) would just wait longer until their chosen price is reached. If they wait longer to buy the hardware, they will probably also buy less games for that system in the long run. Since most of the money is made by selling software, it is in Nintendo's interest to boost the hardware base as fast as possible.
The sales pace of Switch is good, but of course it can be much better.
By lowering the price of the original Switch by $50 they wouldn't reach the people with a $200 budget.
They would also lower their profit margin for the Switch by $50.
The production costs of the Switch Lite are probably much lower than the production costs of the original Switch: no Joy-Cons (including separate batteries + HD rumble), no dock, smaller battery, smaller display...
By selling an entry model with less features & less production costs they can keep their profit margins high.
To reach different target groups with different models. Almost every other company does that (Sony, Microsoft, Apple, Samsung...); Nintendo did that too with different DS and 3DS models.
It's really not that hard to understand.
From what we can see, people aren't waiting to buy Switch in a meaningful way.
If PS4 could sell more than 90 million consoles with a price higher than Switch's, why can't Switch do at least close to that?
it already sold 35 million in little more than 2 years.
People with a budget will always exist, but that hasn't stopped an appealing product to sell very well - if not very, very well.
Yes, a Lite model probably makes them save more money than a 50$ price cut. But that's just an option.
Including games probably works better, specially if those games are the system selling ones. For people with a budget, who are going to buy games anyway, the console just got way cheaper in comparison. Right?
The smartphone comparison might not be a good one, as price diferences are substantial on that market. More, nowdays, these Lite models are presented at the same time as the better models, so, there's no selling something better and then selling something worse based on the premium models.
Nintendo did present newer models over the years, but even then, they always presented something better, not worse. 2DS was the only exception and that was probably due to the backlash of the use of 3D and the fact that people didn't really care that much about it after a while.
None of those reasons are present here for Nintendo to release a Lite model now.
If anything, they should have released a Pro model in anticipation of PS5 and XB2.
This model could have worked after they had tapped all they could have sold with the original Switch. And honestly, i don't think they did that with 2 years on the market.
That's why i don't understand this move now.
Going after price concious people is something you do later in the life cycle of a product, not when the product is maturing.