I suspect the issue is bandwidth. even with a supposedly LTE signal and decent signal strength, 3 bars out of 5, Siri frequently gives me the I can’t connect try later message.
I only use Siri when I have to take notes one handed, usually because I have a sheep in the other. It’s really frustrating.
I suspect the issue is the combination of T-Mobile and Sprint merger plus COVID-19 use of the single cell phone tower in our area but I’m wondering if anyone else has experience the problem.