For the most part, there is no good alternative to google voice, but I still ditched it. I chose a more DIY approach using voip numbers. As you migrate mail away, you still have the old account. Over time more of your email will get migrated to something new. For youtube, use something like pipe-pipe. you get the added bonus of no commercials and sponsor blocks watching privately without a youtube account but still following your favorites. For chat, nostr private messages (0xchat, chatstr, Amethyst), or DeltaChat, among many other platforms, find your tribe and use what they use.