Background: I'm currently working on a critical project at a tech company. The work is good but the salary is less than satisfactory/comparable (I didn't really negotiate - my mistake + personal reasons). I've a job offer from another company that's willing to pay me 30-40K more than what I currently earn. My manager (who knows nothing about the offer) told me that I'll only get a 10K bump after my level-up (which happens in the next month or two) - typical company "policy"...And even if I negotiate, there's noway they will match a 30-40K bump (fact, not a rumor from grapevine).
So, is it wise (or rude? - bridges will be broken) to leave a critical project (that will go live in the next 3-4 months) for a way better salaried job given that the current company would never match a huge salary bump from the offering company? Is it wrong to be selfish and not think about the greater good of the team/project/company?
Also, the offering company prefers that I join within a month or two and they can't wait for more than 3 months because otherwise I'd have seen my product go live and then switch jobs.
Would love to get/hear some advice/opinions. TIA.