I read some old (10+ years) information on whether footer backlinks from the websites that design agencies build are seen as spammy and potentially cause a negative effect. We have over 150 websites that we have built over the last few years, all with sitewide footer backlinks back to our homepage (designed and managed by COMPANY NAME). Semrush flags some of the links as potential spammy links. What are the current thoughts on this type of footer backlink? Are we better to have 1 dofollow backlink and the rest of the website nofollow from each domain?