It's inherently difficult to pick up on bias so I appreciate when it's pointed out

Not so much with housing because the materials and approach to building have changed and that has had a very real impact on longevity (older houses are not over-engineered as such, but they did tend to be built out of heavier/more solid materials because the alternatives didn't exist and using far more labour intensive approaches). That still leads to issues but they tend to be different.

Take UK housing stock, a 100 year old house is not particularly unusual (about 25% of the total stock), most is more than 60 years old. Many of those 100 year old houses are built from solid engineering brick, actual stone, have stone lintels, joists tend to be far thicker/larger than they would be if built now to support thicker/heavier wooden floor boards than would be the norm now too, albeit not as well finished. You'll likely still have a slate roof and heavier rafters to support it. They have/had lime plaster on the walls, lath and plaster ceilings etc.. And would have had internal plumbing/gas/electricity retrofitted at some point in the last 60 years.

That means that the structures tend to be incredibly solid (until someone tries to take out a chimney and fails to support things properly etc..), but also have lots of rough edges, walls aren't quite parallel, nothing is level, insulation (beyond the plaster and ceilings) is poor because the expectation was that the house would need to breathe and would have open fires internally..

Newer builds on the other hand tend to be built using a minimum of material, and using processes that are as light on labour as possible. You have far more complex materials involved, and plumbing, wiring and so on are embedded. The downside of that is that things can go wrong quickly when they do, weathering can be pretty catastrophic, a roof might be expected to last 15-25 years rather than 50-100 years for example, but broadly there is simply less room for wear before it becomes a problem.

There is probably a sweet spot (in the UK at the moment it's likely a 60's built semi/detached house) that balances a decent finish with a solid structure.

There are hundreds of not thousands of houses in this area of my (very old) city that date back to the 1920s (rebuilding after the Halifax explosion). Most streets are all original to that decade; there is the odd new build but due to things like fire or neglect. I wouldn't call it survivorship bias. There's easily three times more construction material in houses of this era than new prefabs.

[deleted]

it's not like large numbers of 100-year-old houses in the places we're talking about have been destroyed (through natural processes - we're not talking about whether buildings can survive a bomb blast).

You can't have a survivorship bias if the vast majority of things from the population survived.

Our landlord also loved using the really caustic industrial drain cleaner because he was too cheap to hire a proper plumber to snake out our back bathroom sink (it's part of the renovations I was talking about). I have a feeling the dozens of applications didn't do our clay sewer pipe any favours

Our next door neighbours failed a couple of years after ours. Apparently many of the houses on our street had theirs taken out the last time they paved and the owners who didn't were told it was a matter of time.

I imagine they were cheaper products used (at the time) due to the reconstruction in our city after the Halifax explosion (look it up if you haven't heard about it, a WWI munitions ship exploded and basically levelled half our city). I was impressed they had a 100 year lifespan, I didn't know they lasted longer!