Baptisms aren't just a Baptist thing, though they generally put more weight behind it than most other denominations that do it. At least from what I've seen.
I was Pentecostal growing up, and a few times a year- generally around Christmas and Easter- they'd do an open baptism and anyone who wanted could get dunked. I went to one church without that big tub behind the pulpit you're talking about- they'd do it in the river nearby. Cold as hell in the winter.
Basically every brand of Christianity that I'm aware of has some form of baptism, though the exact way it's done varies a lot.
Matthew 28:19 is, "Therefore go and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit"
I absolutely hate basically everything about modern logos and UI design. It looks like shit, and for UIs it's not even efficient usually.