"Major issues with script" etc. is super subjective and there are just as many reviews praising the story and characters as criticizing them.
For sure there will be people who don't like the story and characters (just like every BioWare game) but you can't lump that in with the animation and technical issues like it's some objective, universally recognized complaint.
Of course not, but as it isn't a new IP many will be comparing it to the script and range of characters of the previous games. My point largely rides on you do not write a script, story, supporting characters and gamer choice (decisions/consequences) as good as if not better than the previous games and then end up with outlets that gushed over the first 3 dropping off a cliff for this one.
Expectations of calibre of quality is high for Bioware games, sure, but that's only because Bioware has reached lofty heights in the past. Reviews even read like the whole paragon/renegade system has been gimped. Even if ME had nothing on KOTOR, it was still decent enough for consequences for evil/negative decisions. They still pushed you into being a "hero", just a hero that does horrible shit to get to the end goal. Whereas KOTOR actually allowed you to be a bonified villain, and end the game with a genuinely
evil ending.
DA:I was the start of Bioware gutting their own diversity and trying to largely homogenise everything. It's just lazy writing/effort when it comes to a "choose your own adventure" RPG that is suppose to be varied and in-depth like Bioware has done with prior games/series, but ends up feeling like TellTale levels of choice
illusion. Even TellTale games get blasted for it, but everyone now tends to have expectations that a TT game will be a very linear experience simply with an illusion of choice.
Expectations for Bioware and ME were never that defeatist around choice/consequence. If anything it's what had the ME3 ending debacle kick off. Bioware should have learned from that, not take the easy way out and further nuke everything into just being an
illusion. Even their own PR was up on its high horse about "learning" from TW3... Hence I go back to many ME fans do not "give a shit" about cheering around "better combat". It can be appreciated if the overall package retains its level of quality and writing. Like say, Nier! All Platinum did there was say to Taro and Co, leave combat to us (you're quite sucky at it), you do your writing and what the fans loved (which you're good at!). Whoever was lead on the writing/script/choices for ME:A clearly didn't do enough homework, or was just waaaaay out of their depth.
I'll never say it's easy to handle branching paths, multiple takes in VA for options and keep it all together, but as I said above ME1~3 still had a good balance, even if it wasn't quite KOTOR levels. ME:A seems to be further taking what DA:I did and doing it
more. Further eroding the sense of a choose your own adventure RPG, and leaving you with basic binary choices that seem like you should just flip a coin, as what does it matter?