Most modern SNES emulators can open both file types without any issues. Emulators are software programs that let you play old console games on a computer or phone. You might still need a converter for a few reasons:
Emerging tools using LLMs (Large Language Models) can now convert SMC toolpath logic into SFC structured text with 99% accuracy. Tools like GitHub Copilot paired with a custom script can automate what used to take weeks. smc to sfc converter