I fear now that they were entirely correct.
The removal of the NBA allowed the large multiple retailers, both specialist chains and especially supermarkets to dominate the market. They were interested only in pounds, shillings and pence, and not at all in the health of literature per se. A narrow offering of best-selling titles and celebrity memoirs increasingly dominated the market with volumes driven by deep discounting and strong point-of-purchase marketing. Multiple buyers looked only for proven names and formats and the large but increasingly dependent publishers and their literary agents slavishly pandered to them. The independent booksellers, unable to compete on best-seller sales were decimated. There was less and less shelf space available for new authors and as a result, fewer were taken on. Literature suffered.
Cometh the hour, cometh the independent presses. The vacuum created by the implosion of the offerings of the big publishing houses began to be filled by small presses and latterly, ebook publishers. They now drive the new blood in writing and as often as not, dominate the literary prize shortlists. The traditional gatekeepers of publication, the literary agents, have been either overwhelmed, or by-passed by the tide of competent new writers being adopted by the small presses.
Unfortunately, that tide also contains very many poor writers who generate correspondingly poor and barely-edited work, which is self-published, (and yes of course, on occasion, good work is self-published too.) With the exceptions perhaps of erotica and some fantasy fiction, consumers learn to buy books from traditional publishers who will both proof-read and substantively edit their offerings.
But small presses are not equipped to supply the big retailers and the demise of the independent sector means that the shelf space to offer their books on is often not there, leaving only the electronic route to market.
Be careful what you wish for.