I would love a deeper insight into what you mean by this. I can't imagine you're rolling your own http server, database communication layer (as in like, postgresql's jdbc driver), json parsing engine, etc.
For example, there are corners of the Perl ecosystem that have been really stable for a long time. Perl itself is very conservative with backwards-incompatible changes, and DBI, the module that abstracts away database interactions, has been around for a long time (the oldest changelog entry is from 1995, but that was for version 0.58, I'd be surprised if it weren't even older).
Of course, then you don't get the fancy, modern libraries, but going with DBI plus DBD::Pg is probably more efficient than coding your own, and stable enough for a ten-year horizon.
Another approach might be to move the really critical pieces of your software to a much simpler interface. For example, HTTP/2 looks much more complicated than HTTP/1.1, so your software might only implement (a subset of) a HTTP/1.1 server, and then you can use an off-the-shelf reverse proxy to expose it to the "modern" internet. This reverse proxy then is easier to replace, because it doesn't handle the core logic of your application.
Or you go really old-school and use CGI, which is an even simpler interface than writing a HTTP server, and any HTTP server that implements CGI would do as a frontend.
So much so that Perl 6 became a whole separate (doomed?) language after trying to change too much.
(Even if you need to implement something like that from scratch it may be OK, your requirements don't need all of the functionality a third package includes because someone else needed it)
A good case where people use an unnecessary dependency is calling REST (or other http) APIs. If there is a wrapper, people tend to use the wrapper, which is not really needed if the in many/most cases. AT the most use something like requests which is what a lot of things use anyway.
> django-importexport used a savepoint per row making it useless
That is pretty crazy.
It is also another example of something that is easily avoided.