Ok, it's not 2022 yet but close enough since we're in November 2021 at the time of writing.
I've actually been wanting a contender in the Open Source eCommerce space forever as Magento's prevalence for such a long period of time since its release in 2008 is somewhat uninspiring.
Reaction Commerce looked like a great contender and doing a search right now reveals that it may have been bought out my Mailchimp. By the way, congrats to the Mailchimp team on their recent acquisition news. As far as I know, Mailchimp has been largely a bootstrapped company until now - major congrats.
Doing a quick search now for open source ecommerce reveals Saleor which does look pretty damn good I must say. Headless eCommerce was all the craze back say, 3 years ago, now I believe is the actual adoption phase. Magento 2 is headless eCommerce ready - although it might be a bit of a resource hog if you wanted to use it in a headless fashion.
Being somewhat archaic compared to the likes of Saleor, and heavy, is the only real worry I have about Magento. But it is battle tested and proven. I don't believe there is another open source eCommerce project that's processed more dollars than Magento.
Magento Commerce Cloud - to me, feels like a huge fail. I have had first hand experience with it many times over and while I appreciate the level of detailed engineering that has gone into the product, I feel like the cost is better spent elsewhere. You could have a much superior architecture running for less dollars. It's a little clunky and it can slow down your entire development team's time.
The market overall still looks bullish for Magento in 2022. The beauty of Open Source is clearly demonstrated in OpenMage LTS - extending Magento 1's life beyond the official EOL. I do feel like Magento 2 will still be the most popular choice for projects that require heavy customisations, heavy integrations in 2022 and beyond. This is where Shopify just cannot, at all, compete with Magento; now an Adobe product of course.
I hope Adobe has big plans for Magento 3.