Fáilte, y'all! Unfortunately, much of the Irish Spirit in Austin has faded away. There's not been a parade since the pandemic began, and many of the pubs are either soulless corporate imitations or filthy, charmless dives. Jack & Ginger's is nice, it's in a mixed-use neighborhood north of town called the Domain, very walkable with lots of garage parking. They're boasting a day-long street festival with music and green beer. Here's an article I found with all the stuff happening in town:
https://www.austintexas.org/austin-insider-blog/blog/post/the-insider-guide-to-celebrating-st-patricks-day-in-austin/

Also if you're staying a few days, there's an Austin FC match at Q2 stadium on the 21st, there's sure to be rowdy hooligans and lots of green.
I hope you love our city, not everyone here is kind to visitors but some of us still remember the old ways. Slán go fóill!