What would be a good strategy when it comes to salary negotiation in a new job, in the current uncertain job market/economy? Does it really matter whether or not the company is in a "growth sector"?

If you have experience you can negotiate more by justifying with what you have done in your previous roles and how that can benifit your new role.

If you're a fresh grad, you don't have much room to negotiate other than based on your grades which doesn't help that much.

If fresh grad: don't think negotiation works

If you are very senior: maybe

Public sector pegs new joiners to the range of its current employees of the same working experience. Not much wriggle room.

What matters is whether a company has a reputation of high paying.