Three years ago before I joined this forum I knew only of Bitcoin, Litecoin and Dogecoin.  So you coudl say Dogecoin was third most popular coin.
Now three years latter there is way more competition and three years from now will be even more. Dogecoin is now still among most popular coins and I believe it will stay among top50 in three years to come. Three years to come crypto will be so big that being in top50 will mean a lot.