Nothing official.
Some community members have built their own integrations, typically using BroadLink, but sometimes using other bridges. People have mentioned a few of those below.
If you’re willing to use two bridges, there is a community-built project for integrating with an MQTT server on the new smartthings architecture. And it should be pretty easy to find a 433 MHz bridge that can work with MQTT. So that might be a possibility if there’s a particular 433 MHz bridge you want to use and you couldn’t find another integration for it.
Integration Solutions using MQTT
There are other, albeit more expensive, home automation hubs like Homey which do include 433 MHz integration. However, smartthings has not shown any interest in adding more protocols. Their primary customer base is people who have Samsung smart appliances or televisions and don’t have a hub at all. So they seem most focused on supporting Wi-Fi and matter now. (They even dropped zwave from their newest hub, the Station.) so there haven’t been any official announcements, but I wouldn’t expect them to add 433 MHz support. 