Even if those benchmarks showing their models are X% above SoTA actually translate into qualitatively significant improvements (which they probably would), Goog

Even if those benchmarks showing their models are X% above SoTA actually translate into qualitatively significant improvements (which they probably would), Google still has the most to lose even if they do release widely and little to gain. Their best case outcome is to not lose any users, and maybe gain back a few % of the users they've lost in recent years. Search result quality has been declining noticeably for a while now and users want something different.