Don't let it get to you. I just ignore them. Everyone has different opinions on the matter, like you said, and it's just that people see it differently. You're right: the Pokemon series is just supposed to be where we can have fun, and come together as fans. There's good eps and bad eps in each arc.
Myself? Well, personally, I've never liked the change in cast (only because I felt those voices were PERFECT as is, so it was a mistake to replace them). However, I've found the current seasons are still very good, and just executed in a different manner. Pokemon is still Pokemon, though, regardless of how much it has changed over the years. It's not the way I ideally like to see it, but it's still the same show. I've met people on the complete opposite end of where I stand with the series, but we're still all fans of Pokemon. It's still the great series it once was- just changed in ways that are tough for much of the fandom to acclimate to.