We know it's separate to the US Godzilla movies.... But Joe Public doesn't. Joe Public is f*cking dumb
In all seriousness though, some of the regular, popcorn munching, movie goers are easily confused by similar sounding titles, even similar looking fonts on movie posters... I believe (I read) that one of the agreements between Legendary Pictures and Studio Toho was that their 2 movies had some distance between themselves with their physical releases - literally so the public didn't confuse the two productions.
Strange but true.
Personally I liked the lumbering way Godzilla moved, like a steam roller, gave him some heft. I forgive the odd dodgy effect too as the movie only cost about ten million dollars - which is frankly staggering.