It's really hard to predict. 2017 with ICO followed by IEO, DeFi, IDO, NFT. Currently, DeFi and NFT are still very hot; and will continue to exist. I think next could be Web 3 . We can only wait and see what the next trend is.
It seems like the web based application will become a thing after those trends. This time the crypto market already faced another bearish trend and it doesn't look good at all. There will always be a new tech being developed in the cryptocurrency ecosystem and this is the fact.
The trend can't be predicted and im sure that the new trend will be very unique.