If you compare the two coins, Solana and MATIC, Solana is better because it always occupies the top 5 coins. but to introduce me like you, would buy MATIC more than Solana.
We can't judge a coin because of their position in market cap, Solana and Matic are two different coins with different technology, Matic is designed as a layer 2 blockchain technology while Solana is a layer1 and Matic support EVM coins while Solana is a stand-alone layer that has its own technology and very faster than Matic but in term of community trust, Matic win that aspect.
The two are good coin and instead of holding and depending on just only one as investment, it's better to buy and hold the two, you can't say what may happened in the future between the two coins but Matic will come first in my portfolio.