The release of Elden Ring was preceded by "universal acclaim" from reviewers and a Metacritic score of 97, but the PC version is definitely not up to the same standard as the console releases.
Of the current 27,594 reviews on Steam, over 15,000 are "Mixed" mainly due to the performance shortfalls the game is experiencing. The game stutters and struggles to maintain the promised 60fps even when the resolution is set to 1080p and the game is being run with an RTX 3080 Series graphics card.
Publisher Bandai Namco has acknowledged there are problems and apologized "for any inconvenience this may cause and ask for your patience." The key problems identified include the mouse being too sensitive, Easy Anti-Cheat failing to launch under certain circumstances, and most importantly of all, the frame rate "and other performance-related issues during gameplay."
Bandai Namco believes that updating graphics card drives can significantly improve the performance of Elden Ring, but also stated that work is ongoing to improve support for all the different PC configurations out there. In other words, we should expect a patch, which will also likely contain fixes for the mouse and Easy Anti-Cheat issues.
The only non-PC problem Bandai Namco mentions is for the PS5 version, which can lose save data if the console unexpectedly turns off during gameplay. The team knows why this happens and a patch is in the works. Although you can't really stop the PS5 unexpectedly turning off, e.g. you have a power cut, the game will save correctly otherwise so it's a minor problem.
Regardless of the mixed reviews for the PC version, the game has already been a huge success for developer FromSoftware, managing 765,000 peak concurrent players on Steam on launch day. If a performance patch can be released quickly, the Steam review situation should turn around swiftly.