I'm a recovering downtube shifter, but I'm only one yardsale away from a relapse. It's a skill I take for granted after 40 years. You'll get used to it, to the point you shift without looking, and can feel just what gear you're after.
The nice things about friction shifting are being able to precisely tune the derailleur positions to eliminate chatter, no worries about index pitch, and being able to throw the lever over in one move and jump gears.

Before I switched to Ergopower, then Ultegra STI, I didn't shift quite as much, but where it was really noticeable was group rides with modern bikes. I had to anticipate shifts to keep up, and be careful of pacing because of the wider gaps in gears.