Sort of related, I met my half-brother for the first time when I was 33 and he was 28. So I've talked to a lot of people in similar positions about meeting relatives who had been separated at birth. If you meet your mom, you'll probably also meet more siblings.
My experience, and this is shared by a lot of people I've talked to, is that it's fraught.
On the positive side, the initial meeting is kind of wonderful. You'll all be curious about your similarities. My brother likes bike riding, coffee and rap music. What are the odds? It must be genetic.
On the best case scenario side, my brother's mom framed it for me as: "you may feel like you missed 30 years, but if you want to, you still have 50 more years to be brothers."
On the fraught side, there can be a lot of feelings on both sides. A good friend of mine had a couple initial meetings with a brother and then got a message back saying, "That was nice but I don't want to have you in my life. Please never contact me again."
I think the thing is that it's not necessarily worth the hassle. People have deep emotions that they haven't fully processed but have learned to live with. So starting a new relationship comes with the burden of processing those feelings.
The obvious ones are abandonment, jealousy, resentment. The less obvious one is the one that I feel. I'm defensive because I want to protect my relationship and view of my own parents (my dad in this case).
So the tension I have with my new brother is that I'm resistant to fully embracing his view of the situation and that's made it not as connected of a relationship as it could be.
If I were guiding anyone, I would think in terms of your personality. If you need things to be perfect or wrapped up neatly, stay away. These are super messy and there is not likely to be a clean experience.
But if you are ok with messy, there's a lot of positives in the experience.