Thank you for subscribing is not a draft. It's a free opportunity to communicate.
Make the most of it.
Whenever someone subscribes to your newsletter or blog, the system has a provision or may be designed to additionally send out a thank you for subscribing email.
This is typcally a draft but some platforms also allow you to customize this, add links (think crosslinking) and this is critical real yet often ignored real estate for most brands, products, services and experiences.
Make the most of it. Tell your audience authentically how else they can engage with you, how you can troubleshoot or help solve their challenges and what else is a part of your ecosystem.