at any race above 200-400 you cannot run it full speed the whole way. you have to measure out the usage of the tank. we can call it "pace" or whatever, but you aren't really running full speed. therefore sniffing at "tactics" is goofy. even if jakob tries wire to wire front running, he's not actually running a peak sprint. the question is then how much you throttle down to try and maximize the time and placement for the race. or your use of throttle-up or other games within a race. because it's not just speed, it can also be boxing in an opponent where they can't get out of the pack and get away. that costs an increment of time but might benefit placement. you're laser focused on time when i may prefer finishing 1st or 3rd while not running my fastest that week, to tactically put runners behind me on place.
my experience most folks cannot run as good in a race as practice. similar lines, my experience some days you feel great and others merely ok or bad. so it is less predictable than you suggest that you run to some preset pace and time. or what that pace and time should be. also, i think most of us have experienced you feel great and you go too fast and it bites you late. so even there it's properly harnessing a good day.
some days it's rainy. some days it's cold. some days it's hot. some days it's windy.
your competition may be strong, weak, or unknown/unpredictable. you may be slower but wanting to egg the race in a direction that gives you a chance. you may be faster and wanting to try to win but without emptying the tank. if i am 10 seconds slower at 1500 than the best seeds, and this is about place, i may not want to make it a drag race. i may want to encourage the fast kids to slow down and leave me a chance.
front running works best if you are just above and beyond everyone and can cruise the finish. front running is exhausting on windy days or if the competition is more similar to me. if guys B and C are right with me, i want them that increment more tired for the kick finish. i don't want to do all the work. and if i am not putting them away on pace, then i need something at the end.
personally most of my best races place or competition took over from mere pace. like some dude comes up on my shoulder and i am running fast as i can at the end to put them away.
last, at the end of college or HS seasons, or in world-level pro stuff (olympics), you may have heats and rounds to get to the final. you may need to repeatedly finish within a set of places to advance to the next round. or it may be on time but you can't empty the tank to get that time or you won't have anything tomorrow. so you have to figure out what gets you to tomorrow but with most gas in the tank.
for example, different sport, by my select soccer team, coach would rotate some subs in for the semis of tournaments. the starters benched that day would be available if needed, but the idea was to take a calculated risk that we could still win -- the bench guys might be all conference HS players in their own right -- but save some rested players for the tournament final. and once in a while we lost the semi, but it often worked out when we made finals. you win the semi 1-0 or 2-0 instead of 4-0, but you are more rested for the toughest game, playing an opponent who may have run their starters into the ground to get there.
you routinely see folks in olympics vs. diamond league who are either good at heat meets or are only good in a one-off race. now i invite you to go all out in your first heat but then good luck escaping the semi or the final. and as i said above, your chance at success may be something other than a stretched-field drag race at full speed. there are children's stories written about this, no?
sorry but to me these arguments are usually made by also-rans in the middle of the field who because they don't either dominate the race or control the pace, fall behind and see their sole value as, ok, did i run a PR today.
maybe it's i was also a sprinter and hurdler out there doing XC or the 800 but to me it was like "compete," catch and beat the next guy up. work the places. keep fighting til you finish. you do that and you see the value in tactics.