First of all, I think it makes more sense to compare blockchains (Polygon vs Cordano) than coins (MATIC vs ADA).

The main difference between these blockchains is that Polygon is Layer 2 blockchain for Ethereum. Cordano is Layer 1 blockchain.

Polygon is a scaling solution for Ethereum. It can be an advantage and disadvantage. If Ethereum is doing good than it is good for Polygon. If things will go bad for Ethereum then Polygon will definitely be impacted. However, Ethereum is a top blockchain with the support of smart contracts, with the strongest and largest developer community and at the current moment it can be seen as an advantage.

If compare the main parameters as TPS (transactions per second), cost of the transaction, number of dApps, and market cap then Polygon is currently clearly a winner.

Polygon has taken a very big step forward with a lot of partnerships unlike ADA which only does marketting.