How do you generate more B2B leads without relying on paid ads?

I've been researching different B2B lead generation strategies, and a few methods seem to come up repeatedly:

• Create educational content that answers customer questions.
• Optimize your website for SEO so prospects can find you organically.
• Publish case studies that demonstrate real business results.
• Build an email list by offering valuable resources.
• Be active in industry communities and focus on providing helpful insights rather than selling.

I've also been reading from several marketing resources, including https://isbmb2b.com/, to learn more about B2B SEO, lead generation, and content marketing.

For those with hands-on experience: What's been your most effective way to generate qualified B2B leads? I'd love to hear what's worked for you.