Never give something for free.
Your visitors come to your site to solve their problem. If your content or services or product is so good, they would happily give you money. Even if you don’t want to charge for it, you should ask for their email address. Email addresses are also a form of payment.
An email address allows you to have direct access to your audience or customers. You could have millions of followers on every other platform like Facebook, Instagram or Youtube. But if the platform decides to shut you down, you are lost.
Your email list is the best asset you can create.
If you have an audience on any other platform, bring them over to your own website, give something for free, and collect their email address.
So even, if you decide to only launch a free ebook or course, make sure to collect email addresses. If you have just a blog, and even if you get only hundreds of visitors every day, use a lightbox or a slide-in lead form to collect email addresses.