Good grief, that is so ridiculous.
She is a pretty young lady, she looks nothing like Neelix. And while she is humorous at times, it is a needed contrast (IMHO) to the darker and more grim characters that are also in the show.
There's nothing wrong with them having some dark and grim characters as well -- it is personally part of what I find refreshing with Discovery. They don't have supermodels or a cast with Stepford wives uniformity in belief and personality. It is much more realistic in terms of the fact that in real life we tend to encounter a wide range of people who look different and have a wide range of beliefs and personalities.
IMHO it fits into the Trek theme set by TOS, that we need to have folks with the freedom to follow their dreams that have very different viewpoints from each other but understand that ultimately we should be tolerant of even viewpoints that we disagree with so long as they don't violate other people's safety or rights. That was the central part of the McCoy / Spock relationship. They fundamentally disagreed with each other and had opposite personalities, but they learned to put their differences aside to achieve common goals.
Tilly likewise provides a contrast with Burnham. Tilly is friendly and open, Burnham is cold and tends to be stand offish. Burnham is very confident of her ability, Tilly often has self-doubts and questions herself, and so on. They complement and help each other out in their own ways. That is what a real friendship is -- not forcing someone to become like you or just be a plaything to satisfy your wants, but helping them to succeed in what they want to be.
