The activator rails in Minecraft on the switch are still broken after 2 years. When used, no regular minecarts can pass over them without shaking violently and kicking any mob, including players, inside off and stopping abruptly. The other minecarts, the tnt, chest, and hopper ones work as intended. It affects both Creative Mode and Survival Mode.
Thank you for your report!
We're tracking this issue in MCPE-54082, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as working as intended, which means this is not considered a bug and won't be fixed. Please do not leave a comment on the linked ticket.
Activator Rails are supposed to eject any mobs riding in the minecart. If you want to keep the minecart moving, use a Powered Rail instead.
If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
Quick Links:
📓 Bug Tracker Guidelines – 💬 Community Support – 📧 Mojang Support
📓 Project Summary – ✍️ Feedback and Suggestions – 📖 Game Wiki