I'm "lucky" that we can relatively comfortably afford for me to be a SAHP. Don't enjoy it though.
So I want a job, but we don't have enough spare £££ to fund full childcare to get voluntary experience to get into an interesting role (I'm degree and professionally qualified but not in my current location, plus a while out). Because you can't get tax free childcare without both parents working we're stuck - that 20% would make the difference between voluntary work being possible and not!
As I've had a while off temping would be a good way back in through "stepping stone" jobs regaining office experience but temping is a massive gamble if you're paying full time childcare plus wrap around on the off chance - 20% off would reduce the hit.
The old system with childcare vouchers dependent only on that parents job was much better for helping parents back into work as it was easier to cross subsidise the new job (and any necessay interview time or volunteering for experience) from the existing one.
In my personal situation (totally get that I'm privileged) a non "interesting" job would be pretty pointless as I'd just about break even after childcare/travel and overall lifestyle would probably be worse as kids would lose after school activities (after school clubs are limited in what they offer). Flexibility tends to kick in for more senior roles. Just in time to not need it as much because older kids activities are later and can be facilitated after standard hours.
DH is in a field that requires evening and weekend working as well as routine 9-5 (no other options in this field except part time but still as much out of hours). Long term he should get a half day/day off in lieu of out of hours but at this point the actual level of "work" on call doesn't justify it - but he's just as unavailable for childcare overnight/weekends if he's on call sat at home or out all the time as calls involve going to clients urgently!
Doesn't help that I've no damn clue what I want to do, just a few things I know would not suit.
Tried for a couple of grad schemes (civil service type) failed at first hurdle (aptitude tests) before my lack of recent experience was even visible to the recruiters so all out if ideas for a career that fits around childcare hours (including wraparound), doesn't involve long term foreign postings and is sort of "useful".