Who uses workout programs like p90x or similar and are they worth it?

Depends on the goal.

P90x won't get you strong, but it will get your wind up, and you'll be really good at pullups when it's done.

It will work if you follow the program.  There's a million of them out there, just have to find the one for you.  If you dont have the knowledge to create a program give one a try.

Goals?
Goals dictate the program.

I've actually done the X stretch and Recovery and Mobility a few times in the past few weeks.

They aren't ideal for the purpose, but it's easy to follow along.

I did P90x years ago before I had any kids or equipment, you get sick of Tony pretty fast, but it does get your conditioning up and it takes most of the thinking out of it, just push a little.

I did P90x when I was having shoulder issues from benching. I liked the program. I’m currently doing Soflete “Knuckles”.

I signed up for the DDPY program a month back. Someone gave me the old basic DVDs a few months back and I needed to go harder. It was 45$ for a year (vet) on the their app website which gives access to the entire program.

So far so good. I am loosing weight and getting strong and flexible. I unnerved some co-workers a week back when I stood up and folded in half to stretch out from sitting down all day though.

Almost done with Cronusfit Selection Prep.
Super heavy on rucking, but the 20 miler is a good gut check. Once I know for certain my selection of choice is running again (damn corona) I'll do it again, but for now I'm probably going to just stick to my coach's programming and then do some bodyweight/running on top of it.
If anyone could recommend some bodyweight/calisthenic based-programs, I would be much obliged.

I wrote this up after watching a Brian Alsruhe conditioning template video.

It's for either 5 minute warmups or 10 minute conditioning, or both.

Keeps a bit of variety in the day, as you don't really know what you are going to have to do to start or end a workout until you roll a 6 sided die.

Conditioning Templates – Dice
5 Minute Template (double for 10 minutes)
Roll a 6 sided die, do the template that matches number rolled.

1 – Top of Every Minute
Alternate Barbell Complex w/20 Burpees (start with BB complex)
Do complete complex (5 reps each DL, Row, OHP, GM, Back Squat) rest remainder of the minute
20 burpees, rest remainder of the minute

2 – Top of Every Minute
Alternate Barbell Complex w/20 KB Swings (start with BB complex)
Do complete complex (5 reps each DL, Row, OHP, GM, Back Squat) rest remainder of the minute
20 KB Swings, rest remainder of the minute (reduce weight if not completing in 60 seconds)

3 – 90 Seconds Work, 30 seconds rest (For 10 minutes do 5 rounds)
With empty or light loaded barbell do all 3 of day’s exercises (main work) in succession
30 seconds each, then rest 30 seconds
3 rounds

4 – 90 Seconds Work, 30 seconds rest (For 10 minutes do 5 rounds)
With empty or light loaded barbell do all 3 of opposite day’s exercises (main work) in succession
30 seconds each, then rest 30 seconds
3 rounds

5 – Tabata (20 seconds work, 10 seconds rest)
KB Swings/Burpee Alternated
10 rounds

6 – Tabata (20 seconds work, 10 seconds rest)
BB Complex (DL, Row, OHP, GM, Back Squat)
Do each exercise (in succession) for 20 seconds, rest 10 seconds
2 rounds

I've been doing the DDPY program too.  I've been doing it over a year, but kept missing workouts.  Since I had to stay home, I'm on my fourth week of not missing a workout and doing extras.  I've gained flexibility especially in my knees, which are in bad shape.  My back also feels better too.  I recommend it.