Pros
Back in the day, Carbon was an awesome place to work with great talent. They had recruited an amazing team, and built some really cool products.
Cons
There is no bright future ahead for Carbon. They are simply in way too small, way too competitive, no growth markets and have tried for years and invested hundreds of millions (closer to a billion) to find better markets and simply cannot. Its a sad story more than anything else, as overtime there has been decent leadership, but they should have made a massive pivot into a completely different business - they had 700 million+ in funding, enough to reinvent the business 5 times over.
The equity realistically is valued at 0, because companies in this space get ultra low valuation multiples (~1-2), especially if revenue has been flat or down for years (used to work in venture capital). Do not waste your time here any longer, thinking there is any way this will change. They missed the opportunity to sell at the peak of the bubble. Now there is too long an operating history to make the case the future will be different.