And I think it's easy to see small companies lean on the duplication because it's too easy to screw up abstractions without more engineering heads involved to get it right sometimes.
It's not easy to deduplicate after a few years have passed, and one copy had a bugfix, another got a refactoring improvement, and a third copy got a language modernization.
With poor abstractions, at least you can readily find all the places that the abstraction is used and imorove them. Whereas copy-paste-modified code can be hard to even find.
With duplicated messes you may be looking at years before a logical point to attack across the stack is even available because the team is duplicating and producing duplicated efforts on an ongoing basis. Every issue, every hotfix, every customer request, every semi-complete update, every deviation is putting pressure to produce and with duplication available as the quickest and possibly only method. And there are geological nuances to each copy and paste exercise that often have rippling effects…
The necessary abstractions often aren’t even immaturely conceived of. Domain understanding is buried under layers of incidental complexity. Superstition around troublesome components takes over decision making. And a few years of plugging the same dams with the same fingers drains and scares off proper IT talent. Up front savings transmutate to tech debt, with every incentive to every actor at every point to make the collective situation worse by repeating the same short term reasoning.
Learning to abstract and modularize properly is the underlying issue. Learn to express yourself in maintainable fashion, then Don’t Repeat Yourself.