Unreasonable doesn’t even start to capture it. Anthropic being worth 10% of Alphabet is beyond insane.
Investors are forward looking, and market conditions can change abruptly. If Anthropic actually displaces Google, it's amazingly cheap at 10% of Alphabet's market cap. (Ironically, I even knew that NVidia was displacing Intel at the time I invested, but figured that the magnitude of the transition couldn't possibly be worth the price differential. News flash: companies can go to zero, and be completely replaced by others, and when that happens their market caps just swap.)
Anthropic have several similiar competitors with actual real distribution and tech. Ones that can go 10x are underdogs like Google before IPO or Amazon, or Shopify etc. Anthropic current stock is beyond that. Investors no longer give any big opp. to public. They gain it via private funding