Anytime the inning ends, or the pitcher changes, there's a 2 minute pause. Save for the mid-7th inning, when it jumps to 3 minutes. I believe they are longer during the All Star Game, and, maybe, the WS. I didn't notice them longer during the recent Wild Card.
They typically jump to commercial on every break. I watch all my games on delay, and for local broadcasts, it's 3 clicks on the skip button (1.5m) and we're back in the ball park. On national broadcasts, it's 4 clicks and we typically return with the ball in flight or the batter swinging at the first pitch. They cut it really close.
During things like mound visits, they'll slip in an interstitial ad, that's about 10s. There's also voice over ads from the announcers during short pauses (between batters, say), which is almost always team related vs a sponsor, but not as bad as on the radio. On the radio its "First pitch brought to you by...", things like that.
My nits on advertising are the shoulder patches for the players and the stencil on the mound. I particularly hate when a national broadcast layers in something over the batters eye, the locals do not do that. Last year, the Umpires were carrying sponsor patches (some crypto company), I honestly can't recall if they were wearing anything this year. The rotating banners in the back that are in park or green screens overlayed by broadcast behind the plate don't really bother me. I always find it amusing when they turn almost entirely Japanese when the Dodgers are playing.
The pitch clock and shift changes have been great, I love the game. Yankee/Red Sox series last week was a nailbiter. Being at the the local park when the Yankees are in town is a blast.