ETH is the most popular platform than waves, NEM, neo and other platforms as well. It's the most dominant platform right now due to its smart contracts and it may be experiencing a congestion today but its developer is doing something to solve these type of problem and he's proposing sharding.
Ethereum is getting more popularity day by day and people are shifting towards it rather than other coins. Good going Ethereum!
Because it's #2 on most of the crypto market cap websites, investors are relying much to it and believing on what Ethereum can bring them in the future.