Comic decline came long before renumbering was a big deal.
I'm replying to this again because I think it's important to clarify something about the decline of print comics in the US. The peak of the industry was the early 90s- 1991, 1992, or thereabouts. A lot of blame is placed on the industry catering to speculators and collectors over longtime fans and flooding the market with #1s nobody wanted, expensive hologram covers, etc. By the end of the decade the entire industry suffered a massive collapse and Marvel themselves was near bankrupt. There's SOME truth to this, but the primary cause of the industry collapse isn't "too many speculators" it's a distribution war that Marvel Started.
In 1994, looking to squeeze even more money out of the market than they already had as well as solve some self inflicted issues with debt, Marvel bought the third largest distributor of comics in the US, "Heroes World Distribution" to act as their exclusive distributor of all comic book content. Diamond and Capital City were #1 and #2. This was disastrous for a few reasons:
Without Marvel comics to distribute, all of the surviving direct market comics distributors suddenly found their overall sales volume reduced by 35%-40% ... while their operating costs remained constant. In a business where even a single point of discount or volume could translate into huge differences in earnings, these massive losses in sales volume were simply not sustainable. Steve Geppi, owner of Diamond Comic Distributors, responded to this threat to the survival of his business by entering into negotiations to become the exclusive distributor for all the other comics publishers
There were about ten distributors in existence when Marvel bought Heroes World. All of them saw their overall sales drop by up to 40%, but not their costs. Marvel going exclusive meant that virtually all of them were going to go out of business, and Diamond began making aggressive deals to exclusively distribute other non-marvel comic books that Capital City and the others could not match. Capital City made some exclusive deals with a few smaller labels, but this only had the effect of putting those labels out of business.
the other big reason was that Heroes World was a small distributor that in NO WAY was prepared to take on the volume of exclusively distributing the massive chunk of the market that Marvel represented:
Not only did the did the Heroes World Distributing company lack the infrastructure to ship Marvel's weekly sales volume, but the Heroes World management team failed miserably in the PR war to win the hearts and minds of comics retailers. In fact, rather than win over any converts to Marvel, the hassle of having to place two new comics orders each month (sometimes at a lower overall discount), plus paying freight costs on Heroes World shipments, pushed many comics retailers to the brink of closing their stores.
The factor that ultimately made quite a few comics retailers decide to leave the business entirely was the error rate at Heroes World, both in shipments, and billings. The word "fiasco" simply doesn't come close to describing the depth of the problem. The Marvel New York executive team became so distressed at the initial failures at Heroes World that they quickly transferred Marvel Direct Market Sales Manager, Matt Ragone, to the New Jersey Heroes World headquarters to personally intercede. Despite's Matt's prodigious managerial talents, however, the problems simply could not be solved. Just as a case in point, the first week that Heroes World exclusively shipped Marvel comics there were thousands of calls made to the New Jersey Heroes World headquarters to report problems. A new phone system had been installed in anticipation of this possibility, but it was somehow forgotten to ventilate the room where the phone switching equipment was stored. As a result, the internal heat generated by the new equipment caused the entire Heroes World phone system to shut down for three (?) days. Imagine being a comics retailer with no new Marvel Comics that week, irate fans screaming at you, and no way to reach anyone at Heroes World. The frustration and anger levels among comics retailers were as high as I've ever seen them during my 34-year tenure in the comics business. To this day, I still hear from former comics retailers who exited the business during this awful period who still harbor venomous thoughts toward everyone involved with Heroes World.
Heroes World struggled through 1995 and 1996, before being driven out of existence by lawsuits in 1997 as Marvel returned to Diamond, now the only player left in the print comics industry. Those outlets that weren't forced to close by Heroes World massively screwing up for years found themselves in a TERRIBLE position as Diamond's monopoly meant that costs were now far higher than they had been during the era when distribution was competitive. Making things worse, a viable competitor to Diamond isn't possible- as a "no resale" exclusive clause between Diamond and DC prevents a viable competitor from ever arising. Smaller shops were driven out of business totally by the new Monopoly diamond had, and by the end of the decade nearly 90% of local comic book stores had closed.
There are other smaller issues (Marvel was in a precarious position with a lot of debt and made some bad purchases on top of this) but THAT is the big reason why floppy sales are nowhere near their pre-crash levels, and CAN'T return to their pre-crash levels. A new system needs to be established that doesn't rely on the existing distribution network of Diamond to LCS.