First of all, I have to admit that a few years ago, when smartwatches appeared, I was totally wrong. I thought it would be a passing idea and that in a few years people would cast them aside, but that has not been the case. They have evolved, many brands and models have come out, and more are used every day.
According to sales data, mobile phones are more or less stabilized and people change them less quickly, but instead smartwatches continue to increase their sales year after year, and I am clear that they are here to stay, although I still do not see them very necessary. Obviously I'm a bit behind.
In the second quarter of 2022, 13% more were sold than in the previous year, and from now until 2028, some forecasts announce growth of the order of 20%. Which is a lot to grow.
Currently there are 4 brands that control 50% of the sector, and Apple is the largest with 30% of the business and most of the benefits of this market, and then there are many others that stick it out for the crumbs.

***
With the exception of Apple, which keeps its prices around 300 to 400 euros, there are many brands and models that are offered below 100 euros, and even below 50 euros. They offer fewer features, but they do have a few and a lot of people find them useful.
In the coming years, some new functions will be added to smartwatches, such as glucose measurement (there are 400 million people with diabetes in the world), better integration with social networks, faster charges, etc…. so that people continue to buy them. And since they don't cost much, they will.
It is true that the more smartwatches are sold, the less activity bracelets will be sold, since their prices are already very little different, and in general they provide less information. As a data, in the first quarter of 2022 its sales fell by 4%.
In short, it seems clear that smartwatches will gain market share in the coming years, improving the features they already have and adding some new ones.