Telecom for example does Deep PackageInspection. That is rather well kown. Derec made a statement years ago that it is normal for other european isps too. Here is a secondary source for it, i cant find the primary source anymore https://netzpolitik.org/2012/berec-studie-dpi-bei-vielen-providern-bereits-im-einsatz/
If you are succesful in disrupting some dataprocessing doesnt matter, trying to do it is illigal. If you put it there to disrupt crawlers you are trying to disrupt an entities dataprocessing.
If your isp does dpi an archive bomb is able to crash their server. Even if they have measures againt it, it is still illigal because trying it is illigal.
Good question i dont know tbh. Would be an interesting question for a lawyer influencer