Google is testing larger sitenames and favicons again. You can see a considerably larger font used for the sitename (the link in the Google search result snippets) and a larger favicon being tested in the search results.
Shameem Adhikarath spotted this change and posted about it on X - I was able to replicate the test. Here is a side by side version you can click on to enlarge and compare:
Here is a GIF that might make it easier to see:
Shameem shared the source code as well:
— Shameem Adhikarath (@shemiadhikarath) July 22, 2024
Forum discussion at X.
Update - And in 2025:
🆕 Google testing larger fevicon 30 px . for both ads and organic.
— Khushal Bherwani (@b4k_khushal) June 4, 2025
cc @rustybrick pic.twitter.com/cPC519NXsU