[nl]

I great up in the 1980s loving lego, and you couldn't buy just bricks then.

OTOH now you can get https://www.amazon.com.au/LEGO-Classic-10717-Bricks-Piece/dp... very easily (and there are smaller sets that cost a lot less too)

[TedDoesntTalk]

In the USA, you could definitely buy plain bricks in the 1970s. Probably the early to mid 80s, too, but I can’t be certain.