I’m not sure my answer will be in-depth enough for this sub, and I’m not even close to a recorder specialist, but I’ll give it a go.

The first thing to say is that recorders went out of fashion around the middle of the eighteenth century, in other words between what we’d traditionally call the ‘baroque’ and ‘classical’ periods of music. As you mention, Vivaldi, writing in the first half of the century, used recorders extensively, as did other baroque composers such as JS Bach (probably most famously in his aria ‘Schafe können sicher weiden’) and Telemann. As far as I’m aware (could be wrong), neither Mozart nor Haydn, the two great composers of the second half of the century, wrote anything for the recorder, and use of the instrument is hard to find in other contemporary composers.

The second thing to say is that nobody really knows why this is. There’s no documentary evidence talking about why nobody uses recorders anymore for example. There are theories, for example the recorder often being a second instrument for professional musicians, and therefore being dropped as musicians became increasingly specialised. The flute and other wind instruments also developed during this period, which may have seen the recorder lose favour.

This also has to be put in the context of the ‘orchestra’ changing more widely. At its most basic, this means orchestras a) becoming standardised, and b) becoming bigger and louder. For me this second point is probably the mist relevant to your question - recorders simply weren’t loud or ‘cutting’ enough to be useful in the new orchestral setting.

Again this is just a guess, but I think it’s backed up by the fact that there was a recorder revival at the beginning of the twentieth century, when in some circles large loud orchestral music was going o of fashion. Recorders are used in smaller intimate settings by composers such as Britten and Hindemith, for example. I should also say that the recorder revival was part of a more general interest in historical instruments and performance.

To summarise, nobody really knows the answer to your question, but my hunch is that it’s mostly to do with the changing nature of orchestral music, in particular volume or cut-through being important.