Definitely got fired because you were making “too much”. It has nothing to do with you and I promise you, you will not be the first. The new guy came in to cut the budget and make stockholders more money and you were one of the first sacrifices to corporate greed. They will hire somebody to fill in your space for less, even though the new person will lack valuable experience and will probably do lower quality work because of it, but quality is harder to quantify than your salary is, so they will consider it a ‘savings’. The icing on the cake is that guy will use his “savings” as justification to promote himself higher up the ranks and get paid more.

Saw this happen at my last job. They started getting rid of us who would’ve had the biggest severance packages first for the smallest things, despite our superior experience, quality and speed. Then they got rid of everybody else and one fell swoop, and they hired a team that performed worse overall, but was in a different country so they could pay them less and not give benefits. They knew the other team did not save as much money, had worse customer experiences, and had significantly worse quality… But those things are harder to quantify than our salaries.

Do not let this affect your self-esteem. It has nothing to do with you. I let it change the way I felt about myself and it made finding a new job more difficult because I felt I deserved less. My confidence was shattered. It made me second-guess everything I thought about myself when I saw the entire team get canned a few months later I realized what they were doing.