What did exist by 2025:

There were sub-3B text-to-video models;

for example Wan2.1 has a 1.3B variant (alongside a larger 14B one).

comfyui-wiki.com

The open / competitive models often cited as approaching top closed models were generally much larger than 3B (e.g., HunyuanVideo ~13B, Mochi ~10B, Wan2.x 5B/14B).

So unless your bar for “as good as Sora” is defined in a very specific, narrow way (e.g., one benchmark or one style niche), the best defensible answer is:

No

not confirmed / not established that <3B matched Sora by EOY 2025.