Price definitely limits market share and potential upside. The lower priced space will make up a substantial number of the overall share number. And regions that have less discretionary spending power must have the lower priced options to have any options at all. (an aside, the EU average includes the lesser per capita eastern side, lowering the higher per capita western side).
This is in large part why Android proliferates -- because there are low cost smartphone options for regions that must have that low cost option(Xaomi a recent beneficiary). It is also why often inexpensive Chromebooks are seeing huge growth. Microsoft must feel the heat of Chromebook. Mac market share is mostly steady, it's Windows getting hit by Chromebook.
Considerations of the cost of making a device isn't necessarily going to be what determine's the asking price. If a company can monetize the data of the purchaser or there are other forms of expected revenue due to the purchase (Microsoft with X box as an example -- very low on initial hardware purchase, make the money from the software and accessories), they can sell at cost or below cost. Apple's ability to sell at or below cost for Mac is very limited, their biz plan doesn't allow great post purchase monetization except accessories.
Also, Chromebook example, there are a dozen Chromebook hardware manufacturers. This will reduce cost of making it as well as cause downward pricing pressure. Manufacturers will accept very slim margins in the hope volume makes up for it (or those post sale monetization possibilities). These are things MAC cannot compete on and it makes it have a very distinct market share ceiling.
So while Apple could hope to target a 15% share (with that share needing to be around 20% in developed nations to even have a shot), I don't think it is realistic to think Macs could gain the kind of market share that Chromebook is very much trending towards. Of course what happens in two years is an unknown -- I'm speaking just current likelihoods.
I have a particular view on this by being a citizen of a developing country (Brazil). The computer and smartphone markets are nothing alike.
A smartphone is a piece of desire and status in Brazil. The 64 GB iPhone 12 costs $1,600 and the 512 GB iPhone 12 Pro Max costs $2,800. This is a lot for a country in which the GPD per capita is an estimated $7,000 in 2021. A product sold at double the price of the U.S. market for a population that has roughly 10% of the purchasing power. Imagine if the 64 GB iPhone 12 cost $16,500 in the U.S., that is the kind of impact to the pocket.
The iPhone is still popular, but the majority of the population uses Android phones, some of which cost as low as $200. There are reasonable Android phones for sale between $300 and $500, which is still far less than an iPhone SE 2 (around $750). And even the high-end Samsung S21 is more reasonably priced at around $850.
An Android phone can perform similar tasks to an iPhone. It may not be so fast, the camera may not be so good, it does not run iOS, but the basics are all there. You can make and receive calls, take photos, browse the Internet, check e-mails, play games, run apps for anything you may want. And there are more options, with different features, at different price points. The bottom line is, people may opt for either an iPhone or an Android, and they tend to go with the latter for economic reasons.
A computer is different. It is not a status symbol that you can take out of your pocket just to show off. It is a device which is widely used, mainly for businesses, for over a quarter of a century now. Here in Brazil, people are used to Windows PCs.
Macs have had some popularity, especially pushed by the iPhone, but they are not really a thing. And they are truly expensive: the M1 MacBook Air starts at $2,600, and the cheapest 16-inch MacBook Pro costs $6,000. Very unaffordable for a country where the GDP per capita is $7,000: just wonder how many 16-inch Pros would be sold in the U.S. if they cost $58,500 and up.
Many people will still buy iPhones and Macs and iPads from the U.S. and have them delivered via smugglers to avoid paying the hefty tax charged by Brazilian authorities. Still, not many people do this. Market share is low.
As for computers, people use Windows PCs, especially laptops. There are Windows laptops sold for as low as $350, and some better ones for $500 and up. There are some gamer laptops available for $1,000, and the Dell XPS 13 starts at $2,100 with an 11th gen i7 Intel processor, 16 GB RAM, and 1 TB SSD (a similar specced MacBook Air, albeit with the M1 processor, sells for a much higher $5,200).
And people are not generally replacing Windows PCs for Chromebooks. Most of them are sold for $300-$500. Chromebooks are gaining some market due to the low price, but usually for people who want a second device or want something for children to use online at school. This is because, although cheaper than Windows PCs, Chromebooks are much more limited and do not perform the same tasks.
There are some fine Windows PCs that can run anything and still do not cost a fortune. A Dell Inspiron with an 11th gen i5 processor and a 256 GB NVMe SSD costs some $800. The build quality is not great, nor is the screen, but it not only gets the work done as it is pretty fast running Windows and Office.
So, I think Windows will keep the lion's share. Macs may grow a little bit, but they are limited by price. Chromebooks may grow a little as well due to being cheap, but they are limited by functionality.