My main question is whether the above post actually constitues a correct description of reality? And if so, what is the status of potential ongoing analysis of solutions? To me it seems that if now on-chain space is available for arbitrary data up to 4mb per block, this may bloat the chain unnecessarily and make initial block download significantly harder on weak Internet connections.
Many thanks for input! I have not yet seen much debate on this on Twitter or mailing lists despite the quite alarming description of the issue by Porteaux above.