I think 'the north' has a long tradition of Labour politics that doesn't really exist in the Midlands. So even people who live in the posh bits grew up with Labour politics. The suburbs around Birmingham are very conservative (with a small c) and not really any different to the south.
In the circumstances, I think it's a poor result for Labour. Tories and Reform together now match Labour for vote share. No-one is inspired by Starmer and the bland politics of the current version of the Labour Party.
Weird how he was hugely popular in 2017 - and achieved a higher share of the vote than Starmer will, despite the last seven years of Tory misrule. Yet he lost badly in 2019. Many reasons, but the way he was demonised was shocking.