520 million yen, which is roughly 3.5 million usd. This is right after S3 finished airing (peak interest). Multiply that by 4 quarters (taking into account decay-lower revenue for subsequent quarters) and you will have under 13m usd for the entirety of 2025 FY. During the 2024 FY ending in 3/2025, rezero made 27m usd.

For context, the total revenue since the series' creation is roughly 60 billion yen, with probably 99% of it generated from 2016 onwards. Divide that by 9 fiscal years starting from 3/2016 and ending in 3/2025, you will have the yearly average of 6.7 billion yen or 45m usd. That's only the yearly average. The peaks of previous seasons, especially S1, were probably 1x billion.
https://desuarchive.org/a/thread/279008297/#q279011626
This is really bad for kadokawa as a corporation if this is one of their best selling titles right after a new season. Not only is the revenue low compared to other non-kadokawa ips, but its also rapidly decreasing. I suspect the quality of marketing and the lack of figures for the cast, especially hit characters in S3 like Capella and Regulus have some underlying financial reasons. A lack of faith stemming from something that the higherups see. Hit characters from previous seasons like Echidna and Petelgeuse and other female side characters from S1/2 got a lot of figs (41 for Echidna for example). But none for S3