Without an inflationary era in the early universe, you would be left with having to explain 1) the fact that we see very few (none so far) magnetic monopoles; 2

Without an inflationary era in the early universe, you would be left with having to explain 1) the fact that we see very few (none so far) magnetic monopoles; 2) the cosmic horizon problem; 3) the flatness problem. Without inflation, how would you solve these? Inflationary models make predictions about higher moments distribution of fluctations in the cosmic microwave background. These can be measured; so specific models can be falsified.