I dont think the to_timestamp() is the function but the group by or more precise the arregate over ts?

Because even if I keep the ts as raw this does not work.

E.G. with this view definition, it still does not push down the ts filer:

SELECT
    id,
    ts,
    AVG(value) OVER (ORDER BY ts ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) AS avg_value,
FROM
    measurements