Links are still very important, but honestly, link building is a going to be more and more tricky. Check https://www.blackhatworld.com/seo/worst-than-penalties-avoid-seo-maluses.908019/ that we never think about.
I don't know if it really helps but here are some of the practices that I use when I have to deal with backlinks.
Link building must not be a "campaign" but a continuous process. And if you go with a "link building campaign" you have to make sure that something is happening on your website. I m seeing a lot of smart people making this mistake when doing link building. The acquisition curve of backlinks must follow some rules and events (new contents, new products, exceptionnal deals and offers, new feature).
One of my favorite way for getting backlinks is outreach. But outreach is really an art because people receive tons of proposition every single day so you need to stand out. This is how I m doing it: Instead of emailing people and ask them if they could add a link to my website or asking them if they accept blog posts, I send them directly an article in their mailbox. If you take your time for looking the kind of content they publish, you understand the kind of content they like. Everybody needs great, fresh, unique and interesting content, so send them a great peace, remember to add Internal links in the content, so they get a great content hub, and to add your link of course.
That's the best way for my opinion because you don't waste your time asking if they are ok for a guest post, you don't have t explain how you're great, instead show them directly the gold. They have to see it like a present. Doing so, the cost per link increases, but the results are really good.