HELL. NO. Absolutely not. I've been bringing Titania to anything from sorties, through long high index to Eidolon hunts. She is my main frame. After the initial learning period, survival was never an issue. You can easily survive, if you know what you are doing. If you really can't survive at all against level 50 enemies, then that's your fault, plain and simple. Hint: the idea is avoiding damage, not facetanking it. You have built in evasion, distraction in the form of razorflies, easily recastable complete status immunity, oh, and you can zip around at like mach 2, you got the tools, use them. I have put on Quick Thinking just in case, but I rarely ever trigger it below T3 sortie levels.
This is exactly what I'm fearing with the rework: a nerf to her 4 to buff the rest. Problem is: all that'd do is make her objectively worse. She is a single target DPS frame. That's all. She has no real CC, no AoE damage, no team buffs, no meaningful enemy debuffs, nothing. She can do insane damage to a single target and that's about it. And that is fine. I'd rather have a frame specializing in something and be really good at that one thing at the expense of everything else, than these jack of all trades, master of none XP fodder frames we've been getting lately. Nerf her DPS, and even the people who use her will drop her, since she is now not excellent at anything, instead "Meh" at a lot of things.
With that being said, Tribute is utterly misguided as a concept. The key for survival with Titania is keeping the distance and blasting enemies before they'd get close enough to do real damage or while they are occupied by your razorflies. So the idea that I have to fly into the enemy group to pick up a buff with a short duration is a really bad design decision. Especially since these buffs are still meaningless. Dust is cool, but she already has built in evasion and all those damage evading factors I mentioned earlier. I'd wager I save myself a lot more by not going into the enemy group to pick up this buff. Thorns is useless, since she is like the most squishy frame in the game, facetanking any damage with her is just a terrible idea. You can make her return 1000% of the damage, it's still going to be a trash buff, since you'll still get killed all the same. Entangle: meh, I can outspeed the enemies already and it's not gonna do much to help. As for fullmoon: unless you are doing several hours long survival on Mot or something akin to that, you don't need more damage. Like, a lvl 150 eximus heavy gunner melts away in under a second with headshots already.
My recommendation: make all squadmates capable of picking up her buff. That way I can keep killing things from a distance while simultaneously also buffing my team. A win-win all around and it might just make me consider using her 2.
Lantern rework is fine. Not gonna be used a lot, but does it does what it supposed to and is just fine, so it's okay.
Razorwing vacuum is very much welcome. However, I'd really like to ask you to consider making her razorflies either automatically respawn, or recastable without leaving and reentering razorwing form. They are essential for survival, but on higher levels they die pretty fast and constantly getting in and out of razorwing form to get them back is not practical, especially since the blitz is canceled on leaving razorwing. (Personally I'd welcome if Tribute would be replaced by a "summon razorwing flies" ability, making the little buggers available in normal form and easily recastable in razorwing form)
Another 2 recommendations:
1) Increase her base energy. She has the lowest base energy pool of all the caster frames. Right now Arcane energize is pretty much a must to make her not annoying to use, which is a shame.
2) Make spellbound faster to cast. Considering that it's a quickfire ability to stop enemies, cleanse status effects and power up blitz, it really needs to be castable way faster. It's not a powerhouse ability, it's a quick utility one that has no reason to be this slow.