A couple of thoughts:
1. Accepting this is basically the same as saying they own your brain's output 24x7x52. If you're willing to work 24 hours a day, 7 days a week, 52 weeks per year for a company, make sure you're being compensated as such. If they aren't willing to offer such compensation, maybe it's not a good deal.
2. You may be able to negotiate an exception to the clause. Depends on how much they want you, and how much you're willing to invest in fighting the issue.
3. The clause may be moot anyway, depending on local law where you are located. Generally speaking, employment agreement language like that does not override State level law for the state where you're located (assuming you're in the US). Might be worth talking to an attorney if you want to be really sure what your own situation is.
4. The last time I was in this situation I did the whole "disclosure" thing and just played the same game(s) that people do on patents - I made every "prior invention" or "existing project" as intentionally vague and over-reaching as I possibly could, to try to ensure that it would cover anything that I had actually worked on, or anything I anticipated I might work on. I got a little bit of push-back from the company, but in the end I think they accepted what I initially wrote up. Maybe I made some small tweaks, I don't remember all the details now, that was quite some time ago.
I enjoy building stuff, and work is secondary.
Same. My $DAYJOB is just a means to an end, where that "end" is "pay the rent, buy food, etc." I don't derive any of my personal sense of satisfaction or joy in life from my job. I reserve that for the stuff I do on my own.