So here's the deal. I spent 4.5 years with this company managing 2 departments. In this time I managed both departments under budget for the first time in company history and reduced overall operational cost by almost 60%.

This company does advertising. They also have a network of LCD screens that span from coast to coast used for advertising and all managed from a central location. This network was 100% my responsibility.

When I arrived at the company, it was a complete mess. It took me a solid year to clean things up. By the time I was done I had the network at a 99.996% uptime! which is quite the achievement.

During this time I was consistently undermined by the GM of the company. I brought numerous improvements and business plans showing ROI to him over the years only for him to discount them and blow me off. He was a sales person, I'm an engineer. Very different personalities.
Needless to say, we didn't see eye to eye, and it was clear he didn't like me. This also happens frequently with him, the arse kissers get promoted in this company.

Long story short, I was laid off the week prior to Thanksgiving last year. I was told the reason was because they were outsourcing my duties.

In this 4 month gap, they still haven't outsourced anything. In fact, my duties were passed off to our business systems manager. This person knows nothing about electronics or even computers. While I was there, they asked me to train her to be my backup. I then attempted to and reported to them that she wasn't competent enough for the duties and didn't possess the required knowledge.
How did they respond to that? They promote her and I'm then told I'll be reporting to her. WTF?

Anyway, she has completely run the network into the ground. In 4 months, they have spent more than my annual salary trying to fill the void and fix her mistakes. I know this because I'm still close to a lot of people within the company.

The content management software we used while I was there was complete garbage. I pushed for 3 years to have it replaced and spent 18 months testing replacement software. At the end, I found the ideal software for us and negotiated a contract with the company that would have them host the server in the could, set it all up, import schedules and content, deploy the software to all units in the field, all for the same price as our annual license for the current software we all hated. It got shot down.

Low and behold, 2 months before I was laid off, the GM comes to me and says he found some replacement software and that we are moving forward with it. He then turned it over to me to facilitate this and handle the project, then told me it had to be complete by February. He left me with 12 weeks to test, iron out issues, plan, and deploy this. Again, WTF?

When the software was introduced to me, they asked me to do a comparison in detail to the current software. No problem, I nailed It out.
The big difference was that the old software ran in Windows, the new software runs on Linux. Luckily for them, I spec'd all of the computers with this foresight because I wanted to move everything to Linux and I told them this.

So I found out tonight that they new software was never deployed and they scrapped the entire project this week because they just figured out that it doesn't run on Windows. I can't fathom how it took them 6 months to realize this when I told them 6 months ago and they have been working with it this entire time. How does the business systems manager not know this?

After hearing this, I want to email the GM and offer consulting services to him. They are clearly struggling and need help. I know he's too egotistical to accept the offer though, but it gives me the opportunity to passively rub his decision in his face.

I know it's not professional, but I really don't care. I'll never need or use him as a resource and odds are the company will fold in a year. On top of that, I'm in school and completely changing industries anyway.

So what would you do?

TLDR, my old boss is a douche and everyone is laughing at him. Should I make contact to gloat?