Perhaps the difference in attitudes lies in initial training.
Attitudes change and times change.
I was amazed for quite a while when I dear friend of mine who flew just about everything during the last war told me if you hadn’t gone solo after 8 hours questions were asked, by ten you had been transferred to the army.
However a lot of young men lost their lives, some because they were not sufficiently familiar with their aircraft.
Today we live in a society adverse to any risk.
When I started flying, a SEP rating was just that - you could fly just about any SEP, and most clubs would let you do so. Today many clubs look on each SEP as if it was a type rating.
Common sense would suggest there are many singles which are sufficiently similar as to not cause a problem. The same is more or less true of MEPs. However, the differences start to mount up on some types as do the performance. Differences (enough of them) and performance are the two things that will catch you out. The laws of aerodynamics don’t change but the extra speed and inertia of some twins (or even a few singles) do change and may come as quite a surprise.