When comparing Papirus vs Materia, the Slant community recommends Papirus for most people. In the question“What are the best gtk3 themes?” Papirus is ranked 3rd while Materia is ranked 6th. The most important reason people chose Papirus is:
All icons look pleasing, especially with the Arc theme.
Ranked in these QuestionsQuestion Ranking
Pros
Pro Sharp, flat, and fresh
All icons look pleasing, especially with the Arc theme.
Pro Familiar
Used on Lubuntu and BunsenLabs, for example.
Pro Active development
Pro Good support for various DEs
Includes support for Gnome Shell, has a Cinnamon desktop theme, plus supports XFCE, Mate and all the usual suspects.
Pro Under continuous active development
Responsive and helpful developer.
Pro Customizable via Oomox app
Users can build completely personal version easily using Oomox Gui app.
Pro Corresponding theme for Qt/KDE
There is a corresponding theme for the kvantum-engine under Qt/KDE.
Cons
Con Under GNU GPL3
This limits the use elsewhere.
Con Contrast issues / No border around icons
It makes the the fast and makes it simple to add more icons(since you can simply scale them) however the contrast is lost in some situations.
Con No Ideas
It just copies the icon-syle from a different system.
Con Just another material style copy
Con Lacks icon for backintime
Backintime tray icon doesn't display on the panel because Papirus lacks the icon.
Con No Round Corners
Let's be honest Round Corners is a must addition in 2022.