It is possible to downgrade it to 8.4.1 (faster, partially more broken) or even 6.1.3 (fast and old school, many apps don’t work, but there are apps in Cydia to fix stuff).
Biggest issue I encountered is sites requiring TLSv1.3 for HTTPS encryption, and browsers simply do not support that.
Is your iPad on iOS 9.3.5? It is infamously slow.
It is possible to downgrade it to 8.4.1 (faster, partially more broken) or even 6.1.3 (fast and old school, many apps don’t work, but there are apps in Cydia to fix stuff).
Biggest issue I encountered is sites requiring TLSv1.3 for HTTPS encryption, and browsers simply do not support that.