but it seems like it’s enough of a “thing” now
I think it was even more of a "thing" in the past.
I went to a wedding in the early '90s where the bride's mother wore a white (no, not cream/grey/whatever) trouser suit. Presumably her daughter knew and approved, but that's all anyone talked about afterwards.
And there were a lot of disapproving mentions in the press of Princess Grace wearing white to Charles and Diana's wedding.
I agree with PPs who've said that if you have to ask, it's better not to wear it (unless you literally have nothing else suitable and really can't afford anything different).
Again agreeing with PPs, I'm sure you'll look "fabulous" and "amazing". However, I feel that's more the bride's job. And it's possible to look "fabulous" and "amazing" at a wedding (eg Amal Clooney at the Sussex's do) without looking like you think "I wish it was me".
Doubtless there'll be other occasions to wear the suit.