TFA was too safe, but competent and featured charismatic characters and the sequel was expected to expand upon them, the timeframe, world, flesh out the nuances and the conflict. TLJ failed to do that, or anything unique that had not been done in a superior manner elsewhere.
TFA is actively made worse by how TLJ handled the new era and it's characters.
The "it's different so it's good" argument doesn't wash with me, I've seen more than several divisive films that were good or outright masterpieces.
TLJ doesn't even make it to mediocre.