I am sure just about everything has been covered up to this point, but I am not going to read through five pages of internet forum opinion and just put up my two-cents.
Mainly you are training for health and to get ready for competitions, so keep in mind that speed is not important during training, only in competition. A lot of people want speed all the time because their egos are hooked on getting Strava PRs and KOMs or they want to win the King of the Road that day if they happen across another rider, but those things are counterproductive to real training.
So the solution is to do most all of your riding on a slower more durable type of equipment. I know I have gotten far, far less puncture flats on my MTB over the last 30 years than on road bikes, in fact almost zero. I have ridden the MTB with the plastic liners in the tires between the tire and tube, and the big MTB tires and wheels make it much easier to install such equipment than road bike tires do. Also MTB racing and riding is over the same type of hazards road bikes try to avoid at all costs, so the MTB tires and equipment are made to resist flatting.
So my fist suggestion is to just get an old used MTB and put some good brand name tires on it and you will probably have far fewer problems. Save your racing equipment for races and other special occasions when it makes sense to use it.
The heavy-duty road and touring tires and options are a good idea too, but you will want to pick up an extra set of wheels to put them on so you can just swap your fast racing wheels/tires onto your bike when they are needed.
You will probably end up being surprised at how fast MTB equipment is, it normal for good MTB and Gravel racers to average over 20mph in races, so being reliable and tough does not always mean being slow. I can hardly remember getting any puncture flats with my MTB over the last 30 years, but I am sure I got at least one or two, and I put a LOT of miles on it both on and off road with the big knobby tires. Things to think about........