The latest API is always in constant development with new things added all the time. Just like before Helix there were new endpoints constantly being developed for v5, and before that, v3.
For things like bits, you already have viable ways of receiving notifications for bits through a connection to chat and parsing the cheers. If you decide not to make use of parts of the Twitch platform that give you the data you need, and just want to keep using deprecated API endpoints such as v5, then that’s your choice.