This is the biggest reason I've avoided online a lot this year. Only recently did I say screw it and start playing again. Mostly because this Event, while terrible, is hilarious fun running out common lineups to grind innings while working towards Prestige with pitchers. The past couple nights I've played have been pretty stable for the most part. During my run in events today I was seeing the ball well, my timing was very good and it was a pretty fun experience.
Then came the three games in a row where Orel's Sinker looked like 150 and I had to sell out to try and time it. If it was an offspeed pitch I was so far out in front I could have swung twice if the game let me.
There's really no way to combat this, either. Like you said, there are still games as the home team where there is so much latency that pitch speeds are just nonsensical. In the Event I literally don't care since I just want to grind Prestige and I'm using common hitters for the most part. But it definitely affects pitching too, so unless I get a super laggy menu check I still play anyway.
My two biggest complaints this year are latency/pitch speeds and pitch accuracy (which was my complaint last year). I don't think it's a stretch to think these two issues might be related too.
Part of me is holding out hope that the game will play better on Xbox. Even on a wired connection my PS4 just doesn't get anywhere close to the speeds or ping I should get with my internet. My ports are forwarded and I've done all the utility stuff I can on my end. It's usually literally half what my Xbox pulls. I'm sure this is just a pipedream, but I'm still hoping there's a noticeable change.
If this game had a stable online experience and we weren't forced to adjust to pitch speeds due to latency or the nonsensical difficulty change in RS, I feel like it would be a much better experience and the frustration would minimize to a degree.
Will it be different next year? I kinda doubt it. But we'll see.