IIRC, the stock is actually down since the announcement. Nvidia is buying ARM because of its high stock price. The stock already ran up thanks to the AI boom.
Honestly, I work at NVDA and I think the deal is dumb. I don't see what benefit it brings to us. The industry is beginning to move away from ARM, so buying yesterday's technology seems like a bad move.
You're right, it does not seem ARM-acquisition helped or damaged NVDA stock both ways over the past 5 months.
"Moving away from ARM", to where? X86 does not seem like a good destination, RISC V is not there, MIPS/AI-chips etc are not a trend either, I honestly don't know where else the CPU industry can move to.
Honestly, I work at NVDA and I think the deal is dumb. I don't see what benefit it brings to us. The industry is beginning to move away from ARM, so buying yesterday's technology seems like a bad move.