omg the week-later thing is so real. my taurus best friend does this too, brings up stuff from forever ago once she's finally processed it. took me a while to realize she's not being petty, she just needed the time

This pairing is a great example of fire vs. earth pacing. Sagittarius is ruled by expansive, fast-moving Jupiter - you think by talking, in real time. Taurus is ruled by Venus and needs to feel settled before speaking, which is a much slower internal process.

Neither style is wrong, but pushing a Taurus to respond before they're ready usually backfires into exactly the shutdown you're describing. A workaround a lot of Sag/Taurus pairs use: give him an easy out like 'no pressure to respond now, just wanted to put it out there.' That takes the urgency off and often gets you a faster response than pushing would.