Oi! That's my home city you're talking about 😡
Yes, of course parts of it are awful (as with any big city!) but most of it is amazing!
The history, architecture, culture, shops, restaurants are some of the best in the UK - you just need to go to the right parts!
The areas round St Peters Square and Albert Square have loads of cool buildings with historical significance and / or culture. John Rylands Library, Portico Library and Chethams Music School are amazing. Barton Arcade is pretty quirky with some good coffee shops.
The Northern Quarter is very cool, lots of good bars, restaurants, coffee shops...
Ancoats is fab these days (a bit further walk out than NQ) - the marina is lovely to sit on and look at the canal boats with a coffee.
Castlefield is gorgeous - like a little suburb in the centre of Manchester with canals and green space.
St Anne's Square, King St, the area round Shambles Square / Cathedral Square (?) and the Arndale (more high street / commercial) are all good for shopping.
Places to avoid - Deansgate (top end), Market Street, Piccadilly Gardens.