While almost everything is great about Bitwarden, the 5-8 second delay when performing a search is ridiculous (considering I have about 100 records), and I'm considering paying for a better maintained alternative.
Interesting. I just tested on a Pixel 2 XL running the latest public Android 11 OTA version and search doesn't lag at all. Same speed as on a iPhone 11 Pro Max.
Could it be a device issue? I highly recommend you report it to Bitwarden as Android can be a real pain in the ass to test with so many different devices out there with all kinds of strange OEM "optimisations" to the OS.
From the comments, I think this is an Android-specific issue. I use Bitwarden on Android and also find that searches inexplicably take several seconds, especially when you arrive at the search query from the autocomplete popover.
This is exactly where I'm getting the delays. Which is indicative of another problem: in several websites I have to search for the login manually because Bitwarden doesn't find the credentials (according to the Android Firefox/Chrome extensions). This never happened with 1Password.
This is very strange. I have over 480 and never experienced delays in anywhere (MacOS, Android, iOS). Searches only take a second or two once you've started typing in two characters in the search box.
I am on macOS Catalina although that shouldn't matter. I suggest you contact support https://bitwarden.com/contact/