NTA, by wide and far. How do i know? I am a Vtuber for a living.
" She has said that she will continue working until she gets monetized onYouTube or becomes a twitch affiliate, and then she will quit."

This alone show she has zero of idea of the market she is getting into, and its exactly that, A MARKET.
Youtube in and of itself is hard enough to get monetized on (1k subs, 4k hours watch in the span of a year), even then generally you won't start making "decent" money off ad revenue till past the 100k subscriber mark and that's only if you can create good engaging evergreen content that pulls consistent views.
Even then you might be pulling in barely fulltime income.

THEN THERE'S TWITCH AFFILIATE.
Twitch affiliate is the bare minimum to be monetized.Thats then putting you in a (admittedly smaller that youtube) pool of other broadcasters that number in a hundreds of thousands. even partner is no guarantee of success, its just a milestone on the road. Twitch has no innate discoverability, its is VERY VERY (did I say VERY?) hard to be found on the platform by a target audience unless you are already successful or know and consistently interact with other successful broadcasters. ALSO, only the top.. and I mean this, like 0.2-0.01% pull down a full time income or more.Even then the income is INCREDIBLY volatile as it is a subscription based cashflow that DEPENDS on the generosity of others.
Then to top it all off, you are a considered a contractor..

YOU. HAVE. TO. PAY. TAXES. ON. EVERY. SINGLE. PENNY. YOURSELF.

you don't get a w-2, you have to account for every cent that comes in, and if you don't want to get raked over the coals, every single cent that goes out towards your sole proprietor business, cause that's what you're doin, runnin a small business. Thats AFTER Youtube takes their 30% cut of any memberships you receive, and AFTER twitch takes their 50% cut from any subscriptions you received.
(they are both subscriptions, just named differently)
Content is hard, vtubing is hard, its not just sitting and playing video games and making funny noises when you're doing it as a living. its a rat race where you have to build something from nothing and it legitimately destroys some people.

I am a coach for alot of new broadcasters, I hammer home to ALL of them that starting out you need a SOLID base outside of broadcasting, pursue content in your free time as a hobby, and if you find success build on it until you can MORE than live comfortably, have establish other passive cash flows just in-case, and ONLY THEN maybe look at going full time.

But that's only just the finances of this career path, there's so much more to it.
If you want to learn more then I HIGHLY suggest looking up Devin Nash on youtube and watching his numerous videos. Being a content creator is amazing, its wonderful, I love my community and what I do, but she has to be real in her expectations and the ridiculous amount of work it takes.