So, as a player of this game, I will make a few comments here.
Traditionally, pricing in Yugioh has always been dominated more by competitive viability rather than collector value. Not to say that there isn't a collectors market, but it's definitely not to the same size that Pokemon or Magic has been and is often limited to either anime-based archetypes (particularly Dark Magician and Blue Eyes) or fan favorite and historically important archetypes (like Sky Striker).
So, for the most part, the reason Yugioh has been pricey to get into is that often core staples and deck engines often were high rarity with kind of rough pull rates. Just to use personal example, I dropped playing Yubel because Nightmare Throne came out at $40 for an Ultra (a 3 of card) and knew Fiendsmith engine in a few months would be worse (Engraver was a $100 secret rare).
However, once time moves on and new decks come out and banlists hit engine, pricing usually goes down on cards. Furthermore, Konami has been more aggressive with reprints of staples, though we're now in mid transition with the older, cheaper staples starting to show their age and new expensive staples (like Forbidden Crown being $85-90 at time of this writing) taking their place.
Point is, outside of a few beloved archetypes, Yugioh's never had a particularly strong collector's market, even for the specialized rarities like Starlight or Quarter Century rares. Tying so much of product value to competitiveness has led to a lot of this loss of value in long term and a lot of dead sets that go below market value due to not impacting the meta (see the Fire and Water themed Legendary Duelists sets for examples). This has legitimately caused market issues as older sets sit dead on shelves and stores decide to stop carrying Yugioh.
Cue the Overframes and serialized cards, which are meant to start introducing theoretically more beneficial collector value to help keep card value long term and encouraging digging into older sets. Current Overframes are just reprints of existing cards and have been coming in Ultra and Starlight Variety, so outside of something like Branded Mirrorjade (Branded being a beloved lore archetype for years) they're pricey but not impacting mechanical play as there are other versions of the cards available. The Overframes that are new cards are, to my understanding, going to come in non-overframe versions as well so that there's mechanical equivalence without having to drop money on overframes.
That said, they are kind of putting these Overframes into sidesets so far, and Rarity Collection V and Battle of Legends (just saw the list today) are otherwise kind of mid-products, so those Overframes are seriously doing the heavy lifting in value. Konami's set design on these side sets has been a serious criticism of the past. Furthermore, the set the new ones are set to come out has gotten criticism from fans for being $35 a set for basically 18 cards total. It'll probably still sell well cause Overframes, but it will be a good test to see how much patience Yugioh fans will have for Overframes (unless that set list is absolutely cracked with reprints and new cards as well).
tldr: Yugioh's been in desperate need of something with stronger collector value to help maintain long-term value of products for stores, so the Overframes are a welcome addition. At the end of the day, though, Yugioh players really do be meta driven, so scalpers are going to have a rough time of selling seal product cause even the chance of a Overframe isn't going to be enough to get players super excited at buying that much over market price for mid-ass side sets.
