It’s a lot more unusual to have an h after an r than an h after a t, even in German. So if you vaguely remember there’s supposed to be an h somewhere, it intuitively makes more sense after the t.
In German, “th” is uncommon (non-existent?) in words that aren’t overtly borrowed from Latin/Greek, so you get overcompensation like “Ethymologie”. “Rhythmus” trips me up every time.
And that’s Youtube, an entirely different place that isn’t the topic of discussion here and that’s ALSO always been Like That. Never Look At The Comments is received wisdom.