Here's a comparison, yeah it's slanted but it's in response to "before = GOOD, after = BAD":
20s:
40s or 50s
The latter is in every way more appealing while the former is stuck in incorporating "tradition" and doing it cheaply and badly.
And as someone who's gone into countless old buildings, while many are rock solid I can assure you that there isn't some across the board high standard; there are plenty that were slapped together as quickly and cheaply as possible. Renovations are costly because you have structural problems to deal with, old wiring, old plumbing, old radiators, leaky damp basements etc. I can't count the number of houses that had flimsy structures such as 2x6 roof rafters, or where the t&g flooring was nailed directly onto the joists with no subfloor. The old school way of building a bathroom was to put boards in between the joists and fill with mortar.
As far as style, much of DC for example consists of cookie-cutter townhouse developments, developments that are every much the same as any subdivision but attached instead of detached. They don't have "soul" just because they're old, made of brick and have some decorations and likewise, modernism isn't "soulless" just because it eschews ornament and punched windows.