I think Aroma is being developed as a probable replacement for Tiramisu eventually.
It as actually the exact opposite: Aroma release was delayed and delayed thanks to one bug, so the developers decided to exchange the buggy part with a "legacy environment" which they called Tiramisu so the users have something while they wait for Aroma.
Development resources focus on Aroma, so most homebrews have been ported already. There are just two left:
- RetroArch. That's beeing worked on but AFAIK the codes are a nightmare, so Quarky has to rewrite a lot of stuff which needs time.
- Loadiine. Might never get ported as there are better alternatives and no developer interrest. Yes, there are users seeing this differently, like sonictopfan who mentioned the 300 title limit, but even for this limit there's Launchiine which has more developer interrest than Loadiine (but still not enough interrest to finish it. Devs just don't hit the 300 title limit no matter what).
//EDIT: And no, there is no conspiracy going on. Developers are not planning to abandon Tiramisu, they don't plan to hurt you in any way. Its just that no developer has any interrest in Loadiine. Every developer does what he thinks is best, there's nothing stopping devs from porting Loadiine, it's just that no developer sees a valid reason to spend his free time on this. Remember developers don't get payed here, they do all this as their private hobby.
For example my personal reason to not touch Loadiine is that I never ever used it. I have no reason to use it (am not a hoarder but just install the games I am playing, so not even closely reaching the 300 title limit). So why should I spend my free time on something that doesn't help me in any way?