Phi Thanh

I'll start.

I believed that "keyword density" mattered. I spent hours making sure our target keyword appeared exactly 3-4 times per 500 words. I used tools that highlighted which words were "under-optimized." I even re-wrote paragraphs to squeeze in one more mention.

Turns out that hasn't been a real ranking factor for over a decade. Google's RankBrain (2015) and BERT (2019) made keyword density obsolete. These models understand context, synonyms, and user intent. They don't need you to say "best CRM for small business" five times. They know that "top CRM for startups" means the same thing.

What actually matters is topic coverage. Does your page answer the question completely? Do you cover related subtopics that a user would expect to see? Do you use natural language that matches how people actually ask questions?

At YC, investors outlined 8 startups across space, AI, gaming, and agriculture (most of them want to bet on futuristic ideas, e.g. space), and these sparked interest in funding them.

This was the pick:

1. Beyond Reach Labs satellite solar arrays that expand from table-size to football-field size in orbit
   Est. valuation: ~$100M+

2. Byteport next-gen file transfer protocol
   Est. valuation: ~ $30M

3. Hex Security AI agents that continuously hack your system to find vulnerabilities (Rev.: $1M+ run-rate in 8 weeks)
   Est. valuation: ~$100M+

4. Grazemate autonomous drones that herd cattle, track weight, and monitor land
   Est. valuation: ~ $30M

5. GRU Space moon factory turning lunar soil into buildings (starting with a moon hotel)
   Est. valuation: ~$100M+

6. Luel marketplace for real-world human data (video/audio) to train AI models (Rev.: ~$2M ARR in 6 weeks)
   Est. valuation: ~$100M+

7. Pax Historia AI strategy game where players rewrite history (e.g. Rome never falls) 35K daily users
   Est. valuation: ~ $30M

8. Stilta AI agent for patent lawyers (search + analyse IP faster, cheaper)
   Est. valuation: ~ $30M