The size itself isn’t a problem, it’s just a rough indicator of the benefit you get. If it’s only replacing a hundred lines of code, is it really worth bringing in a dependency, and as you point out potentially many transitive dependencies, instead of writing your own? People understood this with left-pad but largely seemed unwilling to extrapolate it to somewhat larger libraries.

You are probably bringing in 10-1000 lines of code for every 1 line you did not have to write (I am sure some good estimate could be calculated?), since all the libraries support cases you do not need. This also tends to result in having to use APIs that are far more complex than they have to be. In addition to security risks.