- Much better tooling & testing
- Excellent editors like VSCode
- Javascript ES6-7 (and the renewed energy of the language)
- GPU accelerated CSS transitions and effects
- Web assembly
- Modern component frameworks & state management
- So many APIs to cover things you used to have to do yourself: payment, transactional email, authentication
- More expressive APIs like GraphQL
- No real need to maintain infrastructure: publish to CDN services; consume APIs.
Compared to development on [favorite-platform-here] it may not be as seamless, but that's an unfair comparison. You have to compare it other forms of cross-platform development, and there the web really shines. It certainly has its flaws and gaps, but I love what's currently happening in the space.