It is simply put. If the new direction of WG is to make stock tech-tree ships "average", but try to compensate for that by adding more and more premiums which are noticeably more desirable, interesting, even superior to tech tree choices, such as the new Asashio and the upcoming Stalingrad, then it will need to consider the game-wide qualitative impact such a design direction will have on the game.
The game will be moving from "f2p" to increasingly "free to try, but not free to play (at high tiers), and definitely not free to enjoy". This is reminding me of the textbook "predatory" freemium design practices from last decade or two, focusing on whales and peer pressure, culminating in games which are all but unplayable without inputting money.
One way WG can avoid moving in that direction, by money-gating players away from better ships to enjoy the game with (or forever stay in the low tiers where it is "free to enjoy"), is to introduce more ways for players to earn doubloons. An insignificant amount, but allowing the player to buy 1 or 2 small to medium premium ships every few months (or a T8+ premium with about half a year), with regular play. Via completing missions, challenges, seasonal events, queuing up with "in need" ship classes to help with game balance, playing well and for the team, etc. Note this is a very different concept from the "lootbox" incentive, which has its flaws, and is more in line with most recent insights in next gen mobile development philosophies. I will not go into either the flaws of the current lootbox design, or all of the highlights of next-gen f2p design (unless someone asks), because that is WG's job, and not the focus of this post.
My main point is still that this design departure is concerning because it is the first major divergence from the WoT line of practices WG has inherited. WoT, while having lots of premiums, stayed away from premium bias for a very long time, and I would think this contributed to its popularity. Further adding options to earn gold via clan wars and other for example, made even the gold-fed premium ammo and other past issues much more bearable than without. But if WoWs becomes known as "the game where premium ships, whole ships, are better than tech-tree ships", then there is little possible to save it, even substantial improvements in graphics, gameplay, and polish. These qualitative issues simply have much more impact than technical or design problems ever will.
Thus, if WG decides to restructure the game around premiums, then it should consider a major revision of the game's core design philosophy, and core systems, so that the game is compatible with such designs. The upcoming CV overhaul is also a good opportunity to be the first of many more restructurings.
So please note that I did not say this "premium bias" is necessarily a bad thing, because nowadays there are more advanced gen designs which even make use of it, but still, keep in mind that for a long time in the past this line of design was nothing short of horrific. WoWs has come a long way since CBT, and design direction changes (more like updates) are inevitable, but given the precarious balance the game still relies on, it is best to not push thy luck, so to say.