I'm sure that it's encouraging to people, but in the end it's very unlikely to change any outcomes. If the project is going to succeed, someone else would have made that first pledge, and the same effect would have happened. It
feels impactful from your end because you're getting involved in so many projects (and getting a lot of thank-you messages), but if all the same projects succeed and fail you haven't actually affected anything.
It's probably also worth mentioning that small pledges (especially $1 ones) are the least efficient in terms of how much of the pledge is lost to fees. A $1 pledge on Kickstarter loses 15% to fees. This is made even worse by having the money come via Patreon, where a similar chunk is lost. So if someone pledges $1/month on Patreon to you, this will end up with a project creator only receiving about 70 cents of it.
I don't mean to be too cynical, it's a great thing to do. I just think it's worth considering if this is really the best approach, or if you could change your method a bit and make more of an impact with the effort and money you're devoting to it.