Both of them were created just for a joke, many doubted the viability of these two coinmemes, but unexpectedly, both of them could be coins that should be owned and indeed it is better to just dump and pump for profit. Shib is fundamentally better, but Doge has a strong community and that's important for its survival. I think Doge will be able to survive for the next 10 years.
Shib already has a very strong community, which creates new opportunities for the coin. Also big investors put money in this asset, which can be considered as more fundamental interest.
No one is better because these are just hype coins, you can invest it now but don't decide to hold it long as eventually, it will become worthless. A coin that is brought by the hype that's why it's successful will not like survive, so I don't like to use the word "better" because you might experience the worst loss if you get hype and join the FOMO.
Doge exists since 2013, which means it is more than 10 years old already. A lot of coins, which now considered to be perspective and worth investing in can`t boast the same time on the market. So we should see meme coins not only as a hype anymore, they are becoming a special market niche.