Yes, historically the RPC endpoint at https://rpc-mainnet.maticvigil.com/ has had a lot of traffic, leading to slower response times and higher latency. To help alleviate this issue, it is recommended to use a more reliable and faster endpoint such as Infura or one of the other MaticVigil endpoints. Additionally, if you are going to be making a lot of requests, it is also recommended to use a caching layer to help reduce the load on the endpoint.