I'm on life 177 on my main, another 30 or so PLs between my 3 farmer alts, I would say that the XP cap increase for reincarnation (and the Drow 32 pt cap) is a relic of a bygone era - so that's valid criticism.
The other things like repeating content, there is SO MUCH content in this game. Not all of it is super polished, some of it is downright oppressive to run, but the DDO Wiki and PsychoBlondie maps are the best way to get through it. Hell, so much of the newer stuff from post-Sharn is linear, I've ran content I never had before like Night Brigade last life for the first time and zerged it. I'm not a ruthless xp/min person, even with 3.8M as long as I have a 30% or 50% pot (ideally) running I can get 1-20 in 3 or 4 nights of solid play for a few hours.
There is a point I think to be made about making the game more approachable. The last time the devs tried was with Korthos Island as a starter area, and then KOTB to soft-introduce quest-crafting, named items, mounts, modern wilderness, and what not. I think we're far beyond the point of a much more streamlined tutorial and starter area - perhaps consolidating some of the older quests into KOTB because at least it's a better first impression than the same 4 beta quests and the annoying ass Korthos "end mission". Add a saga, a new set, and update the Adventure Compendium. Add a "New Player" tab that walks them through and maybe bump up some F2P.
End of the day, this is a 22 year old game that has legacy codebases and tools that go back to AC2 and even before it (I mean, hell, DAT packaging is an AC1 relic). It's owned by a publisher that is in turn owned by a Swedish mega-corp who needs to profit. So yeah, there are some things that are going to force you to spend money like power creep, expansions, new loot, long runs to tick down your XP pots and the meta shifts based on what the EP and one or 2 devs feel like.
It's still a business. I still support it despite running into issues that the "Trying DDO In 20XX" newbie vids on YT and OP do, but I come back because I genuinely love the game and the chase. You're never truly "done", and I lived through DAOC, AC1 and AC2 all being shut down because no one wanted to go to the worlds anymore and I'd hate to see that happen again. So I'll keep buying Sov II's and Ultimates in a hope that I give it another few days of staying up.
That said, there really does need to be more done on the external marketing and retention story. It's one thing to get someone to not chuck themselves off a cliff running beta-era content in 2026, but it is a whole other thing to keep them engaged through the 100s of crafting systems, bonuses, trees, classes, stats, feats, and the reincarnation loop let alone the horrible Epic slog and eventually LTRs too.
If it wasn't for the "Eberron Unlimited" and F2P/"P2W" style of content today, DDO would've shutdown a long time ago. And if I gotta spend $1000 or 2 per year on DDO points for astrals, xp pots, tomes for alts and other meaningless BS well that's fine by me. It's my least expensive hobby after all. It costs me almost 6K to get a new ZCO 8-40 for my ELR rifles, those rifles cost 10-20K, and I cannot shoot all of them at once nor shoot for hours per day everyday. So cost:enjoyment ratio is still on DDO's side, even though a rifle can literally put elk on my table.