I've pasted more than 4095 characters into the terminal, however, I've found that some applications running on the terminal may limit the amount of input they will accept before their input buffers overflow.
For example, I've have problems with some editors accepting large pastes.
However, I've been able to paste large amounts into "cat".
cat >tmp.tmp
and then I would use the editor's import capabilities to read the file.
In the good old days I used vi. These days I use Vim. Not an editor for everyone, but since I've been using this editor family since '85 it is where my fingers feel at home 🙂
Your mileage may vary.