Welcome back. I heartily agree with you, bravo Bioware.
I too am a founder, but have remained with the game throughout all the changes. Like you, I am more of a solo player and will group only to complete content that requires it, but like viewing the cut scenes.
I did finally join guilds, but they were created by myself and 3 other like minded players before the server mergers began. We started the guilds so we could take advantage of the benefits of being in a guild without being hassled. We ended up on the Shadowlands after the mergers. Since I get summers off, I have used that time to personally fund the guild vaults and I even purchased a guild flagship for our Republic side guild.