I think there may be this mystical belief that 100 subscribers is a magical number because when you look up the YT pages for creators, there's this first rung on the ladder there of 100 subs that allows you a few perks etc. I'm not sure how many people even know that, or if it would help if they did.
100 subs to me is a healthy number that, with 3 digits, then looks like you aren't necessarily a new channel.
The conditions and pace which existed when you hit 100 subs and before are probably no different, as other posters have said.
For me 100 subs is my next goal, just because. Then it will be 200, 300 and so on