Local dev isn't the end, it is the beginning. With it it allows you to get further than you would otherwise - and most importantly, when (not if) you do discover a problem on a lower environment (or prod) it gives you a place to try and replicate it. You run everything locally so hopefully you can make a change to mirror the problem... Not a guarantee but at least you have a good starting point.

Also your local dev should try and mirror prod as much as possible.