Yes SHIBA inu Token is better than Dogecoin.
Doge creates 10,000 new coins per block, and each block requires about one minute to be filled. This increases the total supply by 14.000.000 per day, making the repetitive pumps we have seen over the past unsustainable. Read more about this here.

Shiba Inu, on the other hand, does not follow a PoW protocol. As an ERC-20 token, it aims to focus on PoS, and does not issue more coins than those already in the market (read more here). Vitalik Buterin recently got rid of his portion of SHIB, which amounted to 50% of the total supply, leaving about 394 trillion tokens available in the market. While the amount of coins is significantly higher, tokenomics suggest that SHIB might have better profitability chances for new investors, as no new coins enter into circulation.