Oneplay initially decided to build gambling platform on the EOS Mainnet as at the time they found it the best blockchain for Dapp development. However, EOS is saturated with gambling platforms and has become economically nonviable with expensive resource costs.
They have at least 3 reasons to move to Telos:
- Performance and scalability
Telos is the brother chain of EOS, flaunting the same performance and scalability as EOS.
- Lower cost of dApp deployment
TLOS currently trades at around 10x lower than EOS making network (CPU, NET and RAM) resources.
- Support From Telos Foundation
We’re getting support from Telos Foundation to promote our Dapp as well as future plans to make the platform more friendly for developers/users.
Info from Oneplay medium https://medium.com/@oneplay/the-one-play-platform-is-moving-to-telos-network-ecaa8e3e75d8
Basically these 3 reasons are applicable for other projects, and I heard more and more projects will join Telos