You do indeed see Safari updates, however it seems to me that the majority of those updates are security fixes.
The issue here is that Safari is getting slow to adopt new web technologies, and slow at fixing problems with the technologies they have adopted.
This has been a relatively recent change, mostly since the WebKit/Blink split. Before then Apple through WebKit (and thus Safari) often led the way with new web technologies, and they were active participants in broader discussions about web standards, and much more open. It's felt as if they've closed off, and become resistant to event attempting to keep up, much less participate.
The WebKit Surfin' Safari blog shows this quite clearly. Long ago the blog used to be regularly updated. In the last year however there's been just three updates, two of those within the last three weeks.