This might change thanks to a large update that DOOM is getting today, dubbed the 6.66 patch. As noted by Bethesda, this is on top of modes and features that players have already been enjoying like bot support.
Aside from unlocking all multiplayer DLCs, Bethesda also revealed that players could try out "DOOM" for free on specific dates.
Revised Progression System - The revised progression system will alter when and how players unlock additional guns, demons, equipment, and all of the player and weapon customization options. Instead of unlocks being a randomized dice roll, you'll now be able to unlock items through specific leveling requirements and in-game challenges.
Furthermore, players will notice new gameplay.id Software has implemented new Runes in place of Hack Modules. Unlike Hack Modules, they do not expire and do not need to be activated. In multiplayer, Runes are now persistent player abilities earned and included in a player loadout. The new death screen will list out the combination of players, weapon types and damage inflicted. The update's full patch notes can be seen on the official Doom community forums here.
Veteran players will have the option to reset their unlock progression and experience the new progression system fresh, or retain all of their existing guns, equipment, demons and customization options that they've acquired or purchased while unlocking some of the new items in the revised progression system. "Starting at 12:00 pm ET on Thursday, July 20, on Xbox One, 1pm ET on Thursday, July 20 on PC, and 12:00 pm ET on Thursday, July 27 on PlayStation 4, you can try DOOM for free".
Doom came out in May of 2016 to nearly universal critical acclaim, and Id Software has continued to update the game regularly since then. Price drop won't happen until the Doom free-play weekend on Xbox Live. As all progress from the free event is transferred to the full game for anyone that decides to purchase it, this may be an excellent opportunity to see if the game does live up to all the praise it received previous year. The free trial offers the first two levels of the single-player campaign and unlimited play in its online multiplayer. If you like what you play during the Free Weekend, we're offering the full game for $14.99 (US) / £11.99 (UK) / $17.99 (AUS) (digital purchase only).