Oh dear!
The notion that 'all material' would need to be reprinted at the cost of billions is too silly to comment on.
It is even more incredible that a phonics guru like Debbie Hepplewhite does not appear to know the main English spelling rules. Nobody who does would come up with silly spellings like
"simplur tooo spend bilyuns of pOWnds on reprinting all writun wurd mateereal in the English langwaj".
The only tricky words in that sentence are:
to, written, English.
'to' - which has 2 different meanings and sounds (t'go too London) and louts the main spelling pattern 'so, no, go, solo, panto';
'written' has a useless 'w' and
'English' starts with the same sound as 'in India'- it obeys the German spelling system instead of the English one. ('Ingles' in Italian and Spanish.)
I'll remind u what the main English spelling patterns which readers have to learn to sound out are:
a, -able, a-e, ai, air, al, all, ar, are, -ary, -ate, au, augh, aw, -ay,
b, ca/o/ut, -ce, ch, -cial, -cious, -ck, -cy, d, -dge,
e, -e, ea, ear, ee, e-e, ei, eigh, eir, er, -er, ere, eu, ew, -ey,
f, g, ge/i, -ge, gn, h,
i, -ible, -ic, ie, i-e, -ie, igh, ir, is,
j, k, kn, l, le, m, mb, mn, n, ng,
o, -o, oa, oar, o-e, -oe, oi, ol, oo, -oor, or, -or, -ore, -ory,
ou, ough, -ought, oul, our, -our, ow, oy,
p, ph, qu, qua, quar, r, rh,
s, -scious, -se, sh, -sion, -ssion, -sure,
t, -tch, th, -tial, -tion, -tious, -ture,
u, u-e, -ue, ur, -ury, v, -ve, w, wa, war, wh, wo, wor, wr,
x, y-, -y, --y, y-e, z.