Old: Free web stats for one low-traffic website per user, in exchange for displaying a counter or badge on their site. Back when hit counters were more common, that wasn't a big ask, and seeing one was the way other people with websites found out about W3Counter. I included ads on the reports, and offered a paid subscription that would let you add multiple websites to the account and not display a counter on your site. All reports were based on a circular log of about 20000 page views per website.
New: Web stats reports for as many websites as you have for free, with no requirement to display a counter/badge, and no ads on the reports. It's no longer an ad-supported service, just freemium. Users can now upgrade individual websites in their account to paid plans while others remain free, like Cloudflare (I really like how their subscription model works). The per-website upgrade unlocks extended data retention so you can run reports further into the past (no more tiny logs), real-time dashboards, daily/weekly/monthly e-mail summaries of your stats, and conversion tracking features for businesses that sell things and want to track their advertising/promotions.
Was it worth it? From a business standpoint, I don't know if I'll make any more or less money this way. I take big risks that way sometimes. Time will tell. From a personal standpoint, I'll be much happier any time I need to dive into the code to add or change something. Old code needs to die eventually one way or another, just because you can't rely on old language/environment packages forever, lest they pass their EOL and stop getting security updates.