Apart from leeching authority from the host sites, You may as well make backlinks pertinent to your site. Since you hand-crafted the written content on the internet two.0 sites, you can also make it pertinent to your hyperlink you’re going to insert. This can improve the impact of that backlink https://nick-russell.medium.com/how-to-use-web-2-0-sites-for-backlinks-an-seo-guide-970344ee8ba4