I take it this is 26″ wheels? Even so, that’s pretty fast to be spinning out in that gear to be honest and I sort of struggle to believe the whole ‘spinning out’ thing.
The triple is now a 42 max. I honest think this is too big as the bigger the ring just gets bashed on rocks.
I use a 46×12 on my commuter and while this is a 700c wheel the narrow tyres mean it isn’t that much quicker and I rarely spin out even when shadowing buses at 30+mph.
Alot of my roadie pals just use a 39 ring for training and they hit 30+mph on it without worry of ‘spinning out’.
Anyway, there are options for bigger chainrings but you may well have to change the inner ring (you may as well if it’s not used).