It is a known strawman argument. The sanctions weren't introduced because someone was convinced they will make Russia fail or what not, they were introduced because this was the only thing we could do barring military action that nobody was ready for. We knew they will have a negative impact on Russian economy but nobody was hoping for a miracle. Countries like Iran or North Korea were living under sanctions for years and they are much smaller. I haven't seen anybody arguing otherwise, barring YouTube clickbaity "Russia is falling" videos.