This is a simple example, I soloed Tactician and only managed to do it because I could respec all the time.
I gutted Cazador round 1 before he could make a move and turn into mist because I took Alert feat before the fight.
Then after the fight I dropped Alert as I didn’t need too much initiative and dipped one level into cleric for sanctuary for the Raphael fight. Then after that fight I respeced into assasin/ gloomstalker for the House of Grief fight . Etc etc.
I even had Laezel to set her strength to 8 as she got the 23 STR gloves so she ended up as both mele and ranged killer as I poured the extra points into dexterity and Con.
I can get Alert and high initiative before every fight with high initiative boss and then go back into whatever I chose for the rest.
I can change my classes from mele to ranged , to Crowd control based depending on who I am facing, thus bypassing any of the bosses strengths .
How is this a good RP design and how can anyone expect a challenging experience when you can literally fine tune your party all the time?
I don't need the developers to worry about balancing issues that I can completely avoid by not being an idiot. If you felt like you needed to abuse the respec feature to solo Cazador, that's your business, but you could have just not. Why even try to solo the game if you then go out of your way to avoid the combat? It's not even like using a potion of speed where the broken mechanic is right there in your combat interface. That's like four loading screens of effort to literally avoid gameplay. I don't care about that. You can't make a game abuse proof, and there's little point in doing it.
The real problem is when you play the game how it's supposed to be played, and it doesn't offer enough challenge.