I believe there might be a different management for the earlier Rollbit if what you have shared is correct from archive web, and the new management took over in 2020. Also this management knew marketing was the key, and thats why they have spend wisely on their marketing funds and thats helped them grow a lot in the gambling industry.
Although I am not sure about the new management, As far as I know, they rebuilt their their platform from scratch and hired new developers.
Rollbit announced in their blog post
Welcome Back! that they parted ways with the previous team (I guess it was the dev team) and decided to launch Rollbit V2 with a new, more modern, user interface and new features. Among the new features were: levels system (including rakeback and level-up bonuses), improved game navigation, bitcoin deposits and withdrawals, a new affiliate system, coupons, live support, and the trading feature. Everything a modern casino needs!