

The ones I know of are not really masquerading, but rather, funding themselves and/or directly related services (often hosting) via convenient ways.
- Conversations.im (XMPP/Jabber client) is $8 on Google Play, free on F-Droid and is FOSS. Dev runs their own instance.
- OsmAnd+ costs money on Google Play, is free on F-Droid, provides hosting of gigabytes of map data.
- Beeper (bridges from popular chats to Matrix) costs money (subscription I believe), but can be set up on one’s own (I run two bridges on my chat server).
What I do dislike is companies overusing “Open” or “Free” in their own or their product names, with no implication of Free or Open Source software. Similar to slapping “engineer” on non-engineering roles or “manager” on non-managerial ones.
Seeing lots of dislike for Matrix lately. Hosted a Synapse server for many years, never had issues with encryption keys, but have to agree that Element the company (formerly Vector, but they now control the protocol too?) rolls out more new things than they fix old ones. E.g: Element X is slower and calls are not backwards compatible (!). Synapse server keeps getting some (corporate-looking) auth stuff added while on-boarding and registration for plain accounts on self-hosted servers is still a pain. To give them credit, Element app is consistent across platforms (for purposes of convincing people and troubleshooting), and bridges work pretty well.
But it seems any self-hosted solution has its can of worms.
XMPP, being old, implements all modern-expected functionality as extensions, and servers are not guaranteed to have them (common argument). Spam was an issue as well (but simplicity of the on-device and server database allows easy message and attachment deletions). iOS clients for XMPP are meh and require integration with Apple push servers (Snikket and Monal do that, but for how long?)
Tried SimpleX years ago, loved the idea, but it was going through growing pains. In the same vein as metadata leaks for Matrix and XMPP, if you host your own SMP server with a few users, that exposes some info vs using default servers (along with thousands users)