To answer your question - now yes, at the beginning no. I did everything out of a kind of guilt when working very part time hours with three preschool children and it took years to reverse the habit. I'd say that we share the mental load now they're teenagers and I work full time outside the house - I'm simply not physically at home from 7am to 5pm (although I do take a child with me to drop off at the train station 😜 and usually pick him up and/ or a different child up from sports on the way home) and DH works mostly from home.
I wouldn't crochet a toy dog for a new baby or wrote notes from the tooth fairy either (and I am the mother of three children).
I think there's a difference between mental load and sweet frilly stuff tbh.
The crochet dog is the frilly unnecessary elf on the shelf type stuff. Nothing wrong with it and it's very cute and lovely but its as much for the adults as the children, probably more for the adults in all honesty.
Mental load is remembering to put a coin under the pillow perhaps, but writing a note is sweet frills as much for the parent as the child. A bit Instagram really.
Mental load is much more banal, daily grunt work:
do the children have the right clothes clean and everything they need for school/ activities tomorrow?
Have we paid for the activities and the bills and is there petrol in the car, is it taxed and insured and MOTed, is the windscreen washer refilled and do the tires have enough tread? Do any kids capable of taking the bus alone have bus fare/ bus pass with them and a charged mobile with money on the payg if relevant?
Have we thoroughly thought through how to keep the children safe online/ with mobiles and are we monitoring daily if they're still young or taught them various strategies if we choose to let them out and about but not to have a mobile yet?
Do we as a complete family have everything, from hygiene and medical supplies to clean clothing in the right size appropriate to weather and activities to pack to take on holiday next week?
How will child 2 get to football at the same time child 3 has to be at judo and child 1 has a birthday party to be at, all in different places? Has child 1 got a present and do children 2 and 3 have clean kit? What are the logistics of everyone eating a healthy meal, ideally together and at the table, around work, school, football, judo and the birthday party, have we got ingredients for a fairly healthy meal everyone will eat and who will have time to cook it and when?
Has everyone done their homework if relevant and learnt for tests, done reading/ coursework or whatever according to age?