The.com domain suffix is by far the most commonly used and valuable. To put it clearly, Google favors websites with the.com TLD. This is why the.com domain extension is the best for SEO. Due to the fact, that.com domains are the most powerful, they have grown in popularity.
I also have some type in gtlds which have worked well for seo. I have the largest collection of marketing webmaster related domains for sale mostly dot com. Xyz sales are strong but it is people selling their 99c domains at 10x the price.