"It will not be free to IONOS"
You can get an IONOS L-16 SSD dedicated server for $42 a month, and it includes the $62/month Plesk dedicated server plan for free. IONOS has determined it's worth their while to do this.
"Such a sweeping statement. "
Thousands of WordPress plugins and themes offer both free and paid tiers. AWS, Azure, Oracle Cloud, Cloudflare, Gmail, Mailgun, Mailchimp, Apache, PHP, WordPress, your favorite FTP app, etc., offer free services that cost these providers money.
A free Enhance tier would lead to more end-users using it and loving it, more YouTube videos promoting it, more Reddit posts recommending it, and more web hosts pre-installing it.
<sweeping-statement> Literally millions of highly reviewed, free apps and services provide support exclusively through online docs. </sweeping-statement>
"Customers, like with Enhance, can try a service..."
Your point is about adding non-paying customers and the supposed additional support costs. My point is about adding market share, becoming the default cPanel replacement, and not dying like Palm Pilot, Blackberry, Circuit City, Kodak, and Toys R Us. We'll have to agree to disagree.