The phrase "gotten things rolling" implies starting a process or a project. However, there are several antonyms for this phrase depending on the context. A few of them include:
1. Stagnated: If something has come to a standstill, or there's no forward movement, it's best described as stagnated. After the initial surge, the project may have stagnated, and there's no momentum.
2. Halted: If the process has been interrupted, it can be described as halted. Halted tasks or projects could be due to various reasons such as insufficient resources or unforeseen challenges.
3. Abandoned: If a project has been left unfinished, it can be described as abandoned.
4. Rescinded: If a decision has been reversed, it can be described as rescinded.