For the record, it does not appear that b1exch was “built on stealing money” since up until some days ago they were basically just a frontend for doing THORchain swaps.
We don't know how b1exch was funded, but we do know it's operated by b1ack. What we also know is that "b1ack's stash" predates b1ack exchange, this post – /post/4a4f32bd7b9812f58c21 – dates back to June 2024.

Before then were a couple of comprehensive guides published "A Comprehensive Guide to Carding" and "Understanding Card Checkers: A Comprehensive Guide" (/post/3103afe2ba5693580e3b and /post/5e4a42b6e08d6c9ee532), and they otherwise were active in /d/Carding, prior to launching b1ach stash (followed by b1ack exchange sometime later). This post caught my eye however (/post/1bdd851413f6766598e2):

I'll also quote the notable part, in order to avoid any ambiguity here:
My name is b1ack, and I am an experienced and pro member in this scene. I have been involved in carding for many years, and I am here to share my knowledge and expertise with both newbies and pros.
Then according to Cyberint, in September 2025 "b1ack's stash" had domains seized. I checked the latest domain, it remains operational.
In September 2025, the Manhattan District Attorney’s Office seized 12 domain names tied to underground vendors trafficking stolen financial data, including B1ack’s Stash. After an investigation found these sites were selling more than one million stolen credit and debit card records and associated personal information. B1ack’s Stash wasn’t operating in isolation; its infrastructure and the others were sophisticated online marketplaces that let criminals sort stolen cards by bank, geography, and even victim name. All seized domains now display court-ordered notices, and law enforcement continues to investigate the individuals behind and using these platforms
Source:
https://cyberint.com/blog/other/b1acks-stash-a-comprehensive-analysis-of-the-free-1-million-card-leak/Then b1exch was launched, in January 2026 if not mistaken. Hopefully that settles the timeline here in absence of any further explanation.
Alas none of this is against the forum rules as others have pointed out and b1exch (as a service) hasn't done anything wrong here as far as I'm aware.
As long as those supporting/using this service are aware of it's operator running a darkweb market that was previously seized, then there isn't much else to add.