Linux is down slightly after a peak month, but probably that month had Linux over-represented. This month we see English down a bit too, Chinese is up a little.
https://store.steampowered.com/hwsurvey/Steam-Hardware-Software-Survey-Welcome-to-Steam
https://www.gamingonlinux.com/steam-tracker/
I copied the data from gamingonlinux and put it into my own sheet with an exponential trendline (red) and a moving average line (green) to smooth out the variance of the survey. We're definitely trending upwards.
Here's the csv data
0.78, 0.72, 0.80, 0.82, 0.82, 0.77, 0.82, 0.81, 0.84, 0.76, 0.79, 0.80, 0.83, 0.83, 0.81, 0.83, 0.90, 0.83, 0.87, 0.89, 0.91, 0.88, 0.86, 0.89, 0.94, 0.90, 0.90, 0.78, 0.91, 0.81, 0.85, 0.85, 0.86, 0.89, 1.00, 1.02, 1.05, 1.13, 1.16, 1.11, 1.06, 1.02, 1.00, 1.14, 1.12, 1.18, 1.23, 1.27, 1.23, 1.28, 1.44, 1.38, 1.38, 1.27, 0.84, 1.32, 1.47, 1.44, 1.96, 1.82, 1.63, 1.39, 1.91, 1.97, 1.95, 1.76, 1.94, 1.90, 2.32, 2.08, 2.08, 1.92, 1.87, 2.00, 2.03, 2.29, 2.06, 1.45, 2.33, 2.27, 2.69, 2.57, 2.89, 2.64, 2.68, 3.05, 3.20, 3.58, 3.38, 2.23, 5.33, 4.52
Yeah this is a good example of how to look at Steam's hardware survey.
Valve has loads more data than they provide in the survey so they can correct the data to give themselves a much more accurate picture. We just get a monthly snapshot and in aggregate which only shows who happens to have completed the survey. So we can't know the actual absolute numbers and we can't match individual users together like Valve can - but we can see trends in each dataset.
The spiking up and down month to month for OS doesn't matter, the overall trend is up for Linux. It can't tell us actual numbers even using trends, but we can be confident Linux use has been trending up. And while Linux use remains low, it does look like it's tripled or quadrupled in the past.
How much of that is Linux desktop vs Steam deck growth is harder to tell. But in some ways it doesn't matter; even if Linux remains small as a proportion, that is still a lot of users which means the whole Linux gaming ecosystem is healthy.