People who were familiar with Bayo popped off (
Maximillian for example) while people who didn't know her didn't have as strong of an impression initially. I presume that's part of the whole "Bayo didn't end Smash 4 with a bang" comes from.
Which misses the fact that her post-release reception was absolutely a big thing within the Smash community - she got a ton of results and infamy to the point she became nigh-synonymous with Smash 4. That's not part of the initial reactions, no, but post-release reception is a major part of a character's / serie's fame. Similarily, Joker and Hero were talked about for a long while after release (for very different reasons, mind) but being part of the post-release conversation does matter because people talk even longer about the characters.
There are some DLC characters that didn't have a lot of post-release talk:

was considered strong with a really good kill confirm (Jab -> SHORYUKEN!) but he was wildly overshadowed by
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and
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as those two dominated the post-release talk (and the competitive scene, which amplified the post-release talk).

could've been talked about more post-release had the duo gotten more results (like if noted multi-character master Tweek stuck with B-K after getting Top 8 with them in a major tournament), but they've not gotten as much post-release talk as they could've. Arguably not as much as

/
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.