Swedish used to have masculine and feminine gendered nouns historically - and some dialects still do - but they were simplified into two grammatical genders, utrum and neutrum, just as your link says. (There are remnants though, for example “vad är klockan?” “hon är halv fyra”). Masculine and feminine were just squashed into the “utrum” gender, basically, and neutrum is neuter.
Then it might also be useful to know that in these cases, it’s also correct to say “den är halv tio” which might be a safer route for non-native speakers.
Kudos on you learning swedish though, it’s not always easy or completely logical but coming from English a lot of things should come for free.