Look, speech is important. So is protecting the public good. But if one believes in absolutes, rather than takeoffs, they are IMO getting too high on their own supply.
Let’s talk about the trade offs that we have already made.
We're lying to ourselves if we think this couldn't be abused and can implicitly be trusted. We should generally be sceptical of closed source at the best of times, let alone when it's inherently designed to report on us.
To your point of 'as a layman end user what is the cost to me?': more code running on your computer doing potentially anything which you have no way to audit -> compromising the security of whatever is on your computer, and an uptick in cpu/disk/network utilisation (although it remains to be seen if it's anything other than negligible).
My defeated mentality is partly - 'well they're already spying on us anyway'...
Frankly, yes.
“With the first link, the chain is forged. The first speech censured, the first thought forbidden, the first freedom denied, chains us all irrevocably. The first time any man's freedom is trodden on we're all damaged...."