I use WordPress because it offers the best plugins and themes, to me it is more customizable and more secure. I also think the themes are better than blogger themes. With WordPress you can create any type of website you want and they have plugins for almost everything.
WordPress has an edge over Blogger since it has a wide range of plugins. As far as creating a blog site is concerned, you may create a blog site nearly as good as WordPress on Blogger too. However, one huge downside is the fact that unlike WordPress, Blogger has limited themes and third party themes of Blogger are not fully reliable as they have a lot of redirects and if at all, you want to use any third party theme, make sure, you scan it with VirusTotal first. As far as WordPress plugin like YoastSEO is concerned, the same is available outside WordPress and you can look for real time YoastSEO. You can use it for optimizing your Blogger posts. However, the biggest downside of using Blogger is the fact that it doesn't allow you to create sales pages or online stores as good as you can have with WordPress. In simple words, WordPress makes a lot of room for creativity. Blogger may be good for Blogging but not ideal for creating sales page and online stores at all.
If you are new to blogging, go with Blogger to practice things manually, you will learn many things on Blogger, which you cannot learn on WordPress, because in WordPress plugins do everything. Once you learn everything then go with WordPress.
However, if you know about SEO, marketing things and all other related stuff then WordPress is the best!
If you effort go to Wordpress because it is SEO friendly, SEO plugins and easy to use.
If you want free and learn SEO go-to blogger because you can do your on-page activities and it will be a practice for you.