Finnish, by far the majority language, has an alphabetic writing system that is recently reformed enough that it has very consistent sound-symbol correspondences.
The late John DeFrancis
and current researcher and author Stanislas Dehaene
develop historical and international comparisons, backed up by brain imaging in Dehaene's book, to make the argument that initial reading instruction should at its best focus students' attention to sound-symbol correspondences in the written language taught in primary reading instruction.
But initial reading instruction in the United States specifically and in English-speaking countries in general is only half-heartedly done that way,
and when school pupils in English-speaking countries struggle to learn to read independently, they are also likely to struggle to learn other subjects thoroughly.
The best current information I have suggests that initial reading instruction in Finland, whether in Finnish or in Swedish, is better done than much reading instruction in the English-speaking world, and that advantage may account for much of the national advantage Finland enjoys (and partially explain why immigrant families who use Finnish as a second language are the bottom group found in national-level sample testing of Finland for international surveys).
That said, Finns themselves tend to learn speak and read English rather well as a second language by the time they leave school; a practical necessity for international business or travel but not very easy considering the lack of cognates shared between the languages. And despite its consistent orthography Finnish has enough other sources of complexity to be rated as a fiendishly difficult language to pick up as a second language.
On the subject of phonics, it sounds like UK primary education is due to head in the opposite direction to US with compulsory phonics instruction for youngsters, including the hugely controversial recommendation for standardised tests on the ability to pronounce made-up words. I doubt we'll be overtaking Finland any time soon though.